Life Oscillators by Period

Introduction | Known periods
Period: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 20 | 21 | 22 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 39 | 40 | 42 | 44 | 45 | 46 | 47 | 50 | 51 | 52 | 54 | 55 | 56 | 60 | 63 | 64 | 70 | 72 | 75 | 88 | 90 | 100 | 120 | 138 | 144 | 156 | 177 | 256 | 276 | 300 | 312



Introduction

In Life, naturally-occurring oscillators exist of many periods, and almost all additional periods are obtainable using highly artificial mechanisms. The oscillators shown are ones that have known glider syntheses. (Also, some of these oscillators, and their corresponding syntheses, are infinitely extensible.)

The oscillators here could be classified into three broad categories:

The last two methods are useful for creating oscillators with periods that are otherwise unavailable. Unfortunately, it is impossible to use these to obtain prime periods (like 17), prime powers (like 16, 27, 49, 64 and 81), and products of prime powers (e.g. there are no synthesized oscillators of periods 48 and 80, as these both require a period 16 component, and the only synthesized period-16 oscillator can neither spark, be sparked by, nor form objects or pseudo-objects with oscillators of other periods.)

In 1996, Buckingham revealed a suite of track components that use eaters and other still-lifes or sparking oscillators to move a Herschel heptomino (the 20th generation of B heptomino, after it has left behind a block). By combining several of these, in much the same way as one assembles toy train tracks, one can produce looping conduits that take arbitrarily long to cycle a single Herschel. By placing multiple Herschels in such a conduit, one can obtain oscillators of arbitrarily small fractions of such large periods. (These were improvements over his earlier track components that used spark-producing oscillators as still-lifes as stabilizers; unfortunately, those could only produce oscillators whose periods are multiples of those of the spark-producers.)

Oscillators of all periods 58 and above can be obtained in this way. Since Herschels naturally release gliders, this also yields glider guns of all periods 62 and above. (The Herschels collide with each other if closer than 58 generations apart, and they collide with the escaping gliders if closer than 62 generations apart.) Dietrich Leithner has constructed specific Herschel-based oscillators of periods 56 and 57 by adding in one of Buckingham's earlier spark-stabilized sections (as those periods are divisible by 4 and 3 respectively, allowing use of sparkers of those periods).

This is basically a variation of the method described by Conway in the 1970s to construct oscillators of arbitrary period using stable glider-reflectors. (Until recently, most known stable glider-reflectors were derived from the above, turning a glider into a Herschel, shuttling the Herschel, and then turning the Herschel back into a glider.)

In April 2013, Mike Playle found a small 90-degree stable reflector that allows construction of glider-loop oscillators of all periods 43 and above.

At present, Life contains known oscillators of all periods except 19 and 38. (There are also no known non-trivial period 34 oscillators; all known ones consist of independent period 2 and period 17 components).

Furthermore, since the Herschels, eaters, and other small still-lifes can easily be synthesized, syntheses exist for almost all oscillator periods.

Unlike synthesis of still-lifes, synthesis of oscillators is usually much more difficult. It more closely resembles sculpting liquids, chemical synthesis of unstable compounds, or performing open heart surgery on a patient whose heart is still beating. Most of the oscillators with known syntheses are either small, composed of many small and simple interacting pieces, or create seemingly random messes that eventually spontaneously erupt into the object or component desired. Many large pulsators and hassled oscillators were discovered out of searches of random broths, and their syntheses frequently consist of building a few pieces that are similar to pieces seen in the broths that created the desired components (i.e. "art imitating life").

Of course, for any period where guns exist, oscillators must also necessarily exist, since any gun can be turned into an oscillator by adding eaters to eat any escaping gliders.


Known oscillator periods

This is a table of known oscillator periods up to 100. Status is shown in color:

As Herschel conduits exist for all periods 56 and higher, and all their components can be synthesized from gliders, syntheses presumably exist for all oscillator periods 56 and higher. Due to their large sizes, however, no such oscillators are shown.

The Snark reflector allows glider loops of all periods 43 and higher. The Snark can be synthesized, and if such loops can be synthesized, this would mean syntheses would also exist for all oscillator periods 43 through 55. However, no attempt has yet been made to synthesize full glider loops containing multiple Snarks, so this has not yet been demonstrated.

  1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19
20 21 22 23 24 28 26 27 28 29
30 31 32 33 34 35 36 37 38 39
40 41 42 43 44 45 46 47 48 49
50 51 52 53 54 55 56 57 58 59
60 61 62 63 64 65 66 67 68 69
70 71 72 73 74 75 76 77 78 79
80 81 82 83 84 85 86 87 88 89
90 91 92 93 94 95 96 97 98 99
100 101 and higher


Period-1 oscillators

Period-1 oscillators are called still-lifes, and are generally considered separate from oscillators of higher periods. Due to the the large number of still-lifes, these are shown on a separate page.


Period-2 oscillators

Due to the the large number of oscillators, these are shown on a separate page.


Period-3 oscillators

Due to the the large number of oscillators, these are shown on a separate page.


Period-4 oscillators

Due to the the large number of oscillators, these are shown on a separate page.


Period-5 oscillators

Due to the the large number of oscillators, these are detailed on a separate page.

period 5 oscillators

Octagon II [6] Silver's P5 on snake [19] Silver's P5 on snake [14] Fumarole [7] Silver's P5 on python [23] Silver's P5 on eater [24] Silver's P5 above eater [12] Fumarole w/ tub [12] Silver's P5 on very long snake [16] Silver's P5 on canoe [16]
Silver's P5 above shil- lelagh [23] Silver's P5 behind shil- lelagh [17] Silver's P5 on hook w/ tail [31] Silver's P5 above hook w/ tail [15] Silver's P5 above tub w/ tail [14] Fumarole w/ up boat [10] Fumar- ole w/ two tubs [16] Silver's P5 on integral [27] Silver's P5 above long shil- lelagh [27] Silver's P5 on long canoe [20]
Silver's P5 on long hook w/ tail [23] Silver's P5 above extra long snake [20] Elkies's P5 [24] Silver's P5 above tub w/ long tail [26] Silver's P5 on hat [18] Silver's P5 behind tub w/ long tail [22] Silver's P5 above down boat w/ tail [14] Silver's P5 above up boat w/ tail [15] Silver's P5 above long hook w/ tail [16] Pentoad between two eaters [12]
Fumarole w/ tub and up boat [14] Silver's P5 before cis shillelagh [22] Silver's P5 on cis hook w/ tail [30] Silver's P5 above integral w/ hook [30] Silver's P5 above integral w/ tub [30] Silver's P5 on snake siamese snake [27] Silver's P5 on snake siamese carrier [24] Silver's P5 above tub w/ very long tail [30] Silver's P5 on carrier siamese snake [22] Silver's P5 on carrier siamese carrier [19]
Silver's P5 on very long hook w/ tail [27] Silver's P5 above very long shillelagh [20] Silver's P5 on extra extra long snake [20] Fumarole w/ up barge [14] Fumarole w/ fuse w/ tail [16] Silver's P5 above boat w/ long tail [28] Silver's P5 on very long canoe [20] Elkies's P5 w/ tub [28] Silver's P5 on up long hat [21] Silver's P5 on block on table [22]
Silver's P5 on down long hat [40] Silver's P5 behind boat w/ long tail [24] Silver's P5 above block on table [31] Silver's P5 on integral w/ hook [37] Hooks on snake [17] Hooks on carrier [14] Silver's P5 above cis hook w/ tail [43] Silver's P5 on beehive w/ tail [14] Silver's P5 on down barge w/ tail [17] Silver's P5 above claw w/ tail [14]
Silver's P5 on fuse w/ two tails [18] Silver's P5 on up barge w/ tail [16] Silver's P5 above very long hook w/ tail [18] Elkies's P5 w/ claw and pre-block [x] Silver's P5 before cis shil- lelagh w/ tub [x] Elkies's P5 w/ boat [30] Hooks on eater [22] Hooks on python [17] Silver's P5 above long cis hook w/ tail [53] Hooks above eater [15]
Elkies's P5 w/ claw w/ tub and pre-block [x] Pentoad 1h2; Pentoad between eater and bookend and block [19] Block on Elkies's P5 w/ loaf [28] Elkies's P5 w/ claw w/ boat and pre-block [x] Elkies's P5 w/ long bookend and claw and pre-block [x] Elkies's P5 siamese snake [x] Pseudo- barber- pole; Flammen- kamp's P5 [28] Pseudo- barber- pole tie boat [36] Up table on pseudo barber pole [31] Up table below pseudo barber pole [31]
Down table below pseudo barber pole [33] Down table on pseudo barber pole [33] Pseudo barber pole tie up snake [41] Pseudo barber pole tie down snake [41] Pseudo barber pole tie ship [38] Pseudo barber pole tie up carrier [40] Pseudo barber pole tie down carrier [40]
Two pentoads between two eaters [17] Two pentoads between two eaters and a pond [19]
Hooks on two snakes [22] Heart [15] 40-bit P5 oscillator [27] Harbor [34]

The pseudo-barber-pole superficially resembles the whole series of period 2 barber-pole oscillators, but strangely enough, has a period of 5 instead. It forms the basis for a large number of larger period 5 oscillators (and many with periods that are multiples of 5, such as period 10).

Octagon II has eight fingers that can sometimes be used to hassle other oscillators like the period 50 Traffic Jam.

The Fumarole is the smallest oscillator that produces a period 5 domino spark.


Period-6 oscillators

Due to the the large number of oscillators, these are detailed on a separate page.

period 6 oscillators

Unix [6] Up beacon on up candel- frobra [13] Up beacon on down candel- frobra [13] Down beacon on down candel- frobra [13] Down beacon on up candel- frobra [13] Up bipole on up candel- frobra [16] Up bipole on down candel- frobra [16] Down bipole on down candel- frobra [16] Down beacon on cuphook w/ pre- block [17] Up beacon on cuphook w/ pre- block [18]
Up beacon on down cuphook w/ tail [9] Up beacon on up cuphook w/ tail [14] Down beacon on up cuphook w/ tail [12] Blonker [25] Down bipole on up candel- frobra [17] Down beacon on down cuphook w/ tail [13] Up tripole on up candel- frobra [19] Up tripole on down candel- frobra [19] Down tripole on down candel- frobra [19] Up beacon on cuphook w/ pre- block w/ tub [21]
Down beacon on cuphook w/ pre- block w/ tub [20] Up beacon on down cuphook w/ tub and tail [12] Up beacon on up cuphook w/ tub and tail [17] Down beacon on up cuphook w/ tub and tail [15] Down beacon on down cuphook w/ tub and tail [16] Up beacon on up long bookend eating eater [12] Eater eating test tube baby [12] Down beacon on down long bookend eating eater [12] Up beacon on down long bookend eating eater [12] Down tripole on up candel- frobra [17]
Down beacon on up long bookend eating eater [12] P6 w/ block and head [x] Nicolay Belu- chenko's P6 between two eaters [24] Four blinkers around four blocks [12] P6 w/ block and tub [x+5] P6 w/ block and boat [x+7] Short key and skewed pole tie bipole [55] Bent key and skewed pole tie bipole [49] A for All [14]
Jason Summers's P6 [40] Sesqui- unix [12] Merzenich's unix on eater [13] Extremely impressive [30-35] Two cis unices [11] $rats [101-124] 32-bit P6 #1 [72] Two trans unices [11]
Two touching trans- unices [14] Two touching cis- unices [14] 33-bit eater- hassled P6 [50-72] Lonely bee hassled by four toads [19] Ship hassled by two unices [17] Three cis cis unices [23]
Three cis trans unices [16] Three trans trans unices [17] Beluchenko's two unices and block on corner table [24] Merzenich's unix on dual eater-2 [49] Merzenich's 4 clocks hassling 2 siamese unices [42] Unicycle; Four cis unices [28]

All of these with a beacon, bipole, tripole or test tube baby have a pseudo-period of 6, a composite of 2 and 3.

The Unix is the smallest oscillator that produces a period 6 diagonal bit spark.

Extremely impressive is an unusual oscillator. It appears at first glance to be a billiard table, but isn't really, as one of the sides temporarily falls apart, but then re-forms later.


5 Period-7 oscillators

period 7 oscillators

28-bit P7 #1 [57] Burloaf- erimiter [27] Jason Summers's P7 [22] Cheaper (but larger) Burloaf- erimiter [24] 29-bit P7 #1 [59]

The 29-bit P7s (and its related 28-bit minimal form) can have their period increased by 1 with a diagonal bit spark, allowing them to be used in oscillators with periods 7n+1. There are period-8 and period-15 examples.


Period-8 oscillators

Due to the the large number of oscillators, these are detailed on a separate page.

period 8 oscillators

Figure-8; Big beacon [4] Blocker [6] Coe's P8; Tim Coe's P8 [8] Smiley [28] Flammen- kamp's P8 [13] Down table on blocker [9] Up table on blocker [11] Down blocker on cap [9]
Down blocker on down long bookend [11] Up blocker on down long bookend [11] Up blocker on cap [11] Down blocker on up long bookend [11] Up Coe's P8 on table [13] Up blocker on up long bookend [13] Down Coe's P8 on table [13] Down blocker on up long bookend w/ hook [14]
Up blocker on up long bookend w/ hook [14] Up blocker on up long bookend w/ tub [14] Down blocker on up long bookend w/ tub [14] Down blocker on up long bookend w/ hook [14] Up figure-8 and trans mold sharing sparks [13] Down blocker on up long bookend w/ tub [14] Up blocker on up long bookend w/ hook [16] Up figure-8 and cis mold sharing sparks [13]
Up blocker on up long bookend w/ tub [16] Down figure-8 and trans mold sharing sparks [9] Down figure-8 and cis mold sharing sparks [9] Down blocker on down long bookend w/ long hook [15] Down blocker on dock [12] Up blocker on down long bookend w/ down boat [13] Down blocker on down long bookend w/ down boat [13] Down blocker on down table w/ gull [11]
Down blocker on down long bookend w/ up boat [14] Up blocker on down table w/ gull [13] Up blocker on down long bookend w/ up boat [14] Down blocker on up long bookend w/ long hook [15] Up blocker on down long bookend w/ long hook [15] Up blocker on dock [12] Down blocker on up long bookend w/ down boat [13] Down blocker on up table w/ gull [11]
Down blocker on up long bookend w/ up boat [14] Up blocker on up long bookend w/ long hook [17] Up blocker on up long bookend w/ down boat [15] Up blocker on up table w/ gull [13] Up blocker on up long bookend w/ up boat [16] 28-bit P8 #1 [25] Kok's Galaxy [12] Figure-8 and up mazing sharing sparks [9]
Figure-8 and down mazing sharing sparks [12] Two trans blockers [16] Two cis blockers [16] Cauldron, Crucible [26-63] Toad sucked by two figure-8s #2 [17] Toad flipped by two figure-8s #2 [14]
Toad flipped by two figure-8s #3 [17] Toad sucked by two figure-8s #4 [14] Toad sucked by two figure-8s #3 [17] Toad sucked by two figure-8s #1 [12] Toad flipped by two figure-8s #1 [11] 36-bit P8 oscillator [27]
Hertz oscillator [11-14] Tumbling T-tetson; Traffic light hassled by two figure-8s [10] Honeyfarm hassled by four eaters [14] Blocker rephasing P7 [69] Dual Hertz oscillator [20-24]  

Figure-8 is the smallest oscillator that produces a period 8 (delayed) domino spark.

The blocker is the smallest oscillator that produces a period 8 diagonal bit spark.

Kok's Galaxy is produces a period 8 diagonal bit spark.

(See notes under Toad for details about toad-flipper and toad-sucker oscillators.)


8 Period-9 oscillators

period 9 oscillators

Lonely bee; Worker bee [19] Double lonely bee [24] Triple lonely bee [29]
(n lonely bees [19+5n])
Cis triple snacker [25]
38-bit P9 [85] Snacker [17] Double snacker [20] Trans triple snacker [23]
(n snackers [14+3n])

The Snacker is just a pentadecathlon whose period has been hassled from 15 down to 9. It produces a period 9 domino spark. Multiple snackers (for example, the cis triple snacker) make the spark slightly more accessible.


Period-10 oscillators

Due to the the large number of oscillators, these are detailed on a separate page.

period 10 oscillators

Silver's P5 below up beacon on table [25] Silver's P5 on down beacon on table [28] Silver's P5 on up beacon on table [25] Silver's P5 below down beacon on table [35] Pseudo- barber- pole tie bipole [50] Merzenich's 24-bit P10 [40] Pseudo- barber- pole tie tripole [52]
Pseudo- barber- pole tie quadpole [41] 44-bit P10 #1 [65] Merzenich's 4 clocks hassling 2 alternating unices [41] Eight blocks hassling two pulsars [30]

The ones involving pseudo-barber-poles or Silver's P5 have a pseudo-period of 10, a composite of 2 and 5.


2 Period-11 oscillators

P11 oscillators

60-bit P11 #1 [30] Flammenkamp's P11 [95]


Period-12 oscillators

Due to the the large number of oscillators, these are detailed on a separate page.

period 12 oscillators

Up mold on down candel- frobra [17] Up mold on up candel- frobra [18] Down mold on down candel- frobra [17] Down mold on up candel- frobra [18] Jam tie mold [17]  
Baker's dozen; Loaf hassled by two blocks and two caterers [30] 44-bit P12 #1 [142] 45-bit P12 #1 [79] Crown hassled by HWSS emulator and two molds [52]

All of these have a pseudo-period of 12, a composite of 3 and 4.

Note that caterers and/or molds could be used as hasslers in both the first and last oscillators on the bottom row, and either oscillator could also be flipped vertically, yielding 10 distinct versions of the Baker's dozen, and 16 of the Crown.


3 Period-13 oscillators

period1-3 oscillators

Beluchenko's 34-bit P13 [55] Buckingham's 64-bit P13 w/cheap eater-2 [94] Buckingham's 64-bit P13 w/real eater-2 [94]


Period-14 oscillators

Due to the the large number of oscillators, these are detailed on a separate page.

P14 oscillators

Tumbler [6] Up beacon beside burloaf- erimiter [33]

The second one has a pseudo-period of 14, a composite of 2 and 7.


Period-15 oscillators

Due to the the large number of oscillators, these are shown on a separate page.


2 Period-16 oscillators

period 16 oscillators

Flammenkamp's period 16 [36] Blocker and mold hassling two blocks [17]


1 Period-17 oscillator

P17 oscillator

Honey thieves [17]


3 Period-18 oscillators

P18 osc

Two unices hassling block on block [16] Two unices hassling two R pentominos [21] Jason Summers's four eaters hassling four bookends [45]


1 Period-20 oscillator

P20 osc

Fumarole and mold sharing sparks [12]


1 Period-21 oscillator

P21 osc

Down candel- frobra beside up burloaf- erimiter [41]

This has a pseudo-period of 21, a composite of 3 and 7.


2 Period-22 oscillators

P22 oscillators

Jason Summers's Two eaters hassling two things [12] Four eaters hassling two beehives and two blinkers [15]


Period-24 oscillators

Due to the the large number of oscillators, these are detailed on a separate page.

period 24 oscillators

Up figure-8 and up caterer sharing sparks [18] Down figure-8 and up caterer sharing sparks [15] Up figure-8 and down caterer sharing sparks [18] Down figure-8 and down caterer sharing sparks [15] Karel Suhajda's Four blocks hassling two honeyfarms and a beacon [15]
Up figure-8 and up jam sharing sparks [14] Down figure-8 and up jam sharing sparks [14] Up figure-8 and down jam sharing sparks [11] Down figure-8 and down jam sharing sparks [11]

All of these involving figure-8s have a pseudo-period of 24, a composite of 3 and 8.


2 period-25 oscillators

P25 oscillators

2 Honeyfarms hassled by 4 fumaroles and 2 blocks [51-57] 2 Honeyfarms hassled by 4 fumaroles and 2 eaters [51-57]


1 Period-26 oscillator

P26 osc

Up beacon on cis very long beehive on down Beluchenko's P13 [69]

This has a pseudo-period of 26, a composite of 2 and 13.


1 Period-27 oscillator

P27 osc

56-bit P27 #1 [52]


2 Period-28 oscillators

period 28 oscillators

Pulsar hassled by 2 molds, 2 eaters, and 2 blocks [36] Matthias Merzenich's P28 [72]


2 Period-29 oscillators

P29 oscillators

Single P29 pre- pulsar hassler [43] 2 pre- pulsars hassled by 4 eaters and 2 tubs [28]


Period-30 oscillators

Due to the the large number of oscillators, these are detailed on a separate page.

20-bit period 30 oscillators

Queen bee shuttle between trans blocks [6] Queen bee shuttle between cis blocks [6] Queen bee between block and down close eater [6] Queen bee between block and up close eater [6] Trans buckaroo; Queen bee between block and down eater [6]
Cis buckaroo; Queen bee between block and up eater [6] Queen bee between block and down close integral [8] Queen bee between block and up close integral [8] Princess bee, Queen bee between cis close eaters [7] Queen bee between block and down close integral w/ hook [9]
Queen bee between block and up close integral w/ hook [9] Trans buckaroo w/ integral; Queen bee between block and down integral [8] Cis buckaroo w/ integral; Queen bee between block and up integral [8] Queen bee between trans close eaters [7] Queen bee between block and down close integral w/ tub [8]
Queen bee between block and up close integral w/ tub [8] Eureka; Four tubs hassling a pulsar [12] Skewed eureka; Four tubs hassling a skewed pulsar [12] Hectic; Four queen bees shuttling 2 gliders [26]
Capped bad gun [10] Two penta- decathlons hassling two blocks [8]
Double eureka [22] Double skewed eureka [33]

The Queen bee is extremely versatile. It is a shuttle that flips over every 15 generations, leaving a beehive egg, which must be removed; in both cases above, by a block. The Queen bee forms the basis for the first glider gun ever discovered, as well as many oscillators with periods of 30n.

It can also eat gliders many different ways:

In addition to being able to being able to eat gliders in all the same ways a queen bee can, plus several others, the Buckaroo can also naturally reflect gliders 90 degrees, making it useful in constructing glider loops of period 30n.

The "bad gun" is a an arrangement of two queen bee shuttles that forms a glider gun that doesn't quite work, because the escaping glider hits the right shuttle at the last moment; if it were advanced only 2 more generations, it would have escaped. This is rescued and turned into a period 30 oscillator by eating the glider before the right shuttle returns.


2 Period-31 oscillators

period 31 oscillators

Merzenich's 48-bit period 31 oscillator #1 [66] Period 31 glider loop [36]

Merzenich's 48-bit period 31 oscillator generates a diagonal domino spark, allowing it to reflect gliders 90 degrees

The period 31 glider loop uses a special reflector, where a glider hits a mangled honeyfarm, producing a honeyfarm predecessor and a rotated glider. Unfortunately, this only works if a glider is present each cycle, so it cannot be used to produce oscillators whose periods are multiples of 31.


1 Period-32 oscillator

P32 osc

68-bit period 32 oscillator #1 [37]


2 Period-33 oscillators

P33 osc

Two boats and two tubs eating two things [16] Eight pairs of things stablizing each other [68]


1 Period-34 oscillator

P34 oscillator

Honey thieves w/ test tube baby [23]

This has a pseudo-period of 34, a composite of 2 and 17.


1 Period-35 oscillator

P35 osc

Summers's Four eaters hassling two traffic lights and four blinkers [24]


Period-36 oscillators

Due to the the large number of oscillators, these are detailed on a separate page.

period 36 oscillators

Elkies's Two eaters hassling two T tetrominos [9] Elkies's Integral and eater hassling two T tetrominos [10] Elkies's Integral w/ hook and eater hassling two T tetrominos [11] Elkies's Integral w/ tub and eater hassling two T tetrominos [10] Jason Summers's Two eaters and two caterers hassling two B heptominos [34]


2 Period-37 oscillators

P37 osc

124-bit period 37 oscillator #1 [72] Beluchenko's 132-bit period 7 oscillator #1 [40]


1 Period-39 oscillator

P39 osc

Down candel- frobra on down Beluchenko's P13 [67]

This has a pseudo-period of 39, a composite of 3 and 13.


2 Period-40 oscillators

P40 oscillators

26-bit period 40 oscillator #1 [30] Two blockers and a fumarole shuttling a B-heptomino [29]


1 Period-42 oscillator

P42 osc

Up unix on burloaf- erimiter [32]

This has a pseudo-period of 42, a composite of 6 and 7.


3 Period-44 oscillators

period-44 oscillators

Jason Summers's P22 and mold sharing sparks [17] Two pi heptominos hassled by two HWSS emulators and four blocks [68] Two pi heptominos hassled by two HWSS emulators and six blocks [72]


11 Period-45 oscillators

period 45 oscillators

Snacker hassling pentadecathlon #1 [23] Snacker hassling pentadecathlon #5 [23] Snacker hassling pentadecathlon #2 [23] Snacker hassling pentadecathlon #3 [23]
Snacker hassling pentadecathlon #10 [21] Snacker hassling pentadecathlon #9 [21] Snacker hassling pentadecathlon #8 [21] Four pentadecathlons shuttling a glider [14]
Snacker hassling pentadecathlon #4 [23] Snacker hassling pentadecathlon #6 [21] Snacker hassling pentadecathlon #7 [21]


1 Period-46 oscillator

P46 osc

Twin Bees [8]

Twin Bees is one of the simplest natural shuttles found in Life, and one of the first to be found. It produces useful plumes of clean debris, which is is why it was used in some of the earliest glider guns found. The toxic unstable eggs at the ends can be eaten in many different ways, by blocks, eaters, even hats. Interestingly, it is possible to eat the engine prematurely, altering its period to 54. By controlling the eating mechanism, the same shuttle can alternate between the two periods, resulting in the period 100 Centinal.


2 Period-47 oscillators

period 47 oscillators

P47 pre- pulsar hassler [52] Beluchenko's P47 hassler [146]


1 Period-50 oscillator

period 50 oscillator

P50 Traffic-jam [34]

This is the simplest of many similar traffic-jam oscillators. The Traffic light push reaction has a period of 25, but one traffic light will patiently wait for another to move into position, so it is easy to construct traffic jams of periods that are not multiples of 25, by using appropriate sparkers of other periods. For example, a period 40 traffic jam sparked by period 8 sparkers, and the period 110 Traffic circle, where period 5 sparkers hassle traffic-light predecessors arranged in a large square.


1 Period-51 oscillator

P51 oscillator

112-bit period 51 oscillator #1 [76]


2 Period-52 oscillators

P52 oscillators

Four eaters hassling lumps of muck [17] Four molds hassling four block pairs [31]

The second oscillator has 30 trivial variations. First, there are six different versions of the outside. Any of the mold hasslers can be reversed to hassle the opposite side of the moving signal: none (as shown), one, two (cis), two (trans), three, or four molds can be reversed. Second, there are five different versions of the inside. The block pairs are quiescent except when passing an unstable signal. Multiple signals can be in the same interior as long as they are at least 16 generations apart, so there can be one signal (as shown), two signals (separated by 16+36, 20+32, or 24+28 generations), or three signals (separated by 16+16+20 generations). The additional signals can be injected into the interior from any side by repeating the last step of the synthesis.


2 Period-54 oscillators

period 54 oscillators

Four eaters hassling twin bees [12] Two twin bees, each hassled by four eaters, hassling pentadecathlon [35]


1 Period-55 oscillator

P55

Pseudo- barber- pole tie P11 hassler [64]

This has a pseudo-period of 55, a composite of 5 and 11.


1 Period-56 oscillator

P56 oscillators

Two blockers hassling B heptomino [19]


Period-60 oscillators

Due to the the large number of oscillators, these are detailed on a separate page.

P60 oscillators

Two pentadecathlons shuttling glider [7] Toad flipped by 2 penta- decathlons #1 [10] Toad sucked by 2 penta- decathlons #1 [10] Toad sucked by 2 penta- decathlons #2 [10] Toad flipped by 2 penta- decathlons #2 [10] Toad sucked by 2 penta- decathlons #3 [10]
Twirling T-tetsons; 8 toads spinning a pulsar [40] Penta- decathlon and mold sharing sparks [8]  

(See notes under Toad for details about toad-flipper and toad-sucker oscillators.)


1 Period-63 oscillator

P63

Snacker on burloaferimiter [49]

This has a pseudo-period of 63, a composite of 7 and 9.


1 Period-64 oscillator

P64

Merzenich's P64; 4 blocks hassling 2 beehives and 2 R pentominos [12]


1 Period-70 oscillator

P70 oscillator

78-bit P70 #1 [35]


1 Period-72 oscillator

P72 oscillator

Two blockers hassling R pentomino [19]


1 Period-75 oscillator

P75 oscillator

Three pentadecathlons shuttling a glider [10]


1 Period-88 oscillator

P88 oscillators

Pi heptomino hassled by six eaters [16]


1 Period-90 oscillator

P90 oscillator

Original diuresis; 4 pentadec- athlons hassling two bookends [20]


1 Period-100 oscillator

period 100 oscillator

Centinal [16]

The Centinal alternates between the natural period 46 and hassled period 54 versions of Twin Bees, by creating a pair of blocks in the middle and then destroying them.


4 period 120 oscillators

large P120 oscillators

Cis Penta- decathlon and figure-8 sharing sparks [8] Four pentadecathlons rotating a pulsar [17] Two queen bees and two pentadecathlons shuttling a glider [15]
Trans Penta- decathlon and figure-8 sharing sparks [7]


1 Period-138 oscillator

P138 osc

Nivasch's P138 [12]


1 Period-144 oscillator

P144 oscillators

Flammenkamp's P144 [15]


1 Period-156 oscillator

P156 oscillators

4 blocks hassling 4 pi heptominos, with eaters eating gliders [55]

This is actually a period 156 glider gun that shoots two pairs of gliders along one set of diagonals, then 78 generations later, two pairs along the other diagonals. Pairs of eaters eat the gliders, turning this into an oscillator. (There are other mechanisms for eating the gliders that double the period to 312.)


1 Period-177 oscillator

P177 osc

Period 177 pulsator [24]

This oscillator can reflect gliders 90 or 180 degrees in several different ways.

Because it is so large, a larger, earlier synthesis is included in a separate file.


1 Period-256 oscillator

P256 oscillator

Buckingham's 104-bit P256 [41]

This is actually a period 256 glider gun that shoots one glider every 64 generations and rotates 90 degrees, resulting in a one glider in all four diagonal directions every 256 generations. Four eaters eat the gliders, turning this into an oscillator.


1 Period-276 oscillator

P276 oscillator

Four twin bees shuttling traffic-light-and-glider predecessor [35]


1 Period-300 oscillator

P300 oscillator

Centinal and penta- decathlon creating temporary block [22]


3 Period-312 oscillators

period 312 oscillators

4 blocks hassling 4 pi heptominos, with 4 beehives eating gliders [24] 4 blocks hassling 4 pi heptominos, with 4 loaves eating gliders [24] 4 blocks hassling 4 pi heptominos, with 4 ponds eating gliders [24]

This is actually a period 156 glider gun that shoots two pairs of gliders along one set of diagonals, then 78 generations later, two pairs along the other diagonals. Here are three different ways of stabilizing this, each of which doubles the period to 312:

These mechanisms (as well as the true period 156 one.) can be used together in any combinations, and the syntheses are simple combinations of the ones above. It is also possible to create other variations that have different symmetry classes (e.g. rotational symmetry by flipping two of the beehives, orthogonal symmetry with orthogonal glide symmetry by alternating the phase of adjacent pairs of boat-bits, diagonal symmetry with diagonal glide symmetry by alternating the phase of opposite pairs of boat-bits, etc.)



Other types: still-lifes, pseudo-still-lifes, oscillators, pseudo-oscillators, oscillators by period, pseudo-oscillators by period, guns, multi-colored Life, basic spaceships and pseudo-spaceships, exotic spaceships, spaceships flotillae, puffers, constellations, methuselahs, not quite stable objects.

See also: Life objects sorted by: counts, frequency of occurrence, cost in gliders, name, size in bits, or type.

Home page | Life page

Copyright © 1997, 1998, 1999, 2013, 2014 by Mark. D. Niemiec. All rights reserved.
This page was last updated on 2015-02-19.