# Conway's Game of Life

### Mathematics and Construction

###### Pattern Files for Chapter 2: Still Lifes

RLE, Macrocell, or LifeHistory code for all patterns that are displayed as figures in Chapter 2: Still Lifes are provided here. These patterns can be viewed in-browser by clicking on the "Show in Viewer" link near the code, or the patterns can be viewed and manipulated by copying and pasting the RLE code into Game of Life software like Golly.

All pattern files from this chapter in a .zip archive file (0.03 Mb)
###### Figure 2.1: small still lifes

All still lifes with seven or fewer live cells.

RLE code: Select all
```x = 57, y = 14, rule = B3/S23 8bo19b2o6b2o6b2o8bo\$2o5bobo8bob2o5bobo5bo2bo5bo2bo5bobo\$2o6bo9b2obo5b 2o7b2o8b2o6bobo\$55bo7\$bo16b2o10bo7bo7b2o\$obo15bobobo6bobo5bobo6bobo\$2o 19b2o5bobo6bo2bo7bo\$28b2o8b2o8b2o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.2: strict non strict

Three strict still lifes (left) and two non-strict still lifes (right).

RLE code: Select all
```x = 47, y = 13, rule = B3/S23 40bo\$39bobo\$39bobo\$40bo\$b2o6b2o7b2o7b2o\$o2bo5bo2bo5b2o7b2o6b2o7b2o\$b2o 8b2o21bo2bo5bo2bo\$18b4o5b2o6b2o7b2o\$18bo2bo5b2o\$40bo\$39bobo\$39bobo\$40b o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.3: pseudo not pseudo

The leftmost block is a strict still life, the bi-block is a pseudo still life, and none of the other arrangements of blocks here are pseudo still lifes.

RLE code: Select all
```x = 56, y = 10, rule = B3/S23 33b2o\$33b2o2\$7b2o5b2o7b2o\$2o5b2o5b2o7b2o9b2o17b2o\$2o32b2o17b2o\$7b2o7b 2o8b2o\$7b2o7b2o8b2o\$54b2o\$54b2o! #C [[ GRID THEME BOOK ]]```
###### Table 2.1: small still lifes table

A selection of small still lifes. The still lifes on the left are strict, while the ones on the right are pseudo.

RLE code: Select all
```x = 83, y = 186, rule = B3/S23 8bo\$2o5bobo\$2o6bo6\$bo\$obo\$2o6\$10b2o6b2o6b2o8bo\$ob2o5bobo5bo2bo5bo2bo5b obo\$2obo5b2o7b2o8b2o6bobo\$37bo6\$bo9bo6b2o8b2o\$obo7bobo5bobobo5bobo\$o2b o5bobo9b2o7bo\$b2o6b2o19b2o6\$b2o7bo8b2o7b2o9bo\$o2bo5bobo7bobo6bobo7bobo 29b2ob2o\$o2bo6bobo7bobo8bo7bobo28b2ob2o\$b2o9bo8b2o9bo7bobo\$12b2o17b2o 8bo6\$2bo8bo11b2o5b2o\$bobo6bobo10bo6bobo41bo\$bobo6b2obo7bobo8bo37b2obob o\$2ob2o8bo6bobo9bobo35b2ob2o\$13b2o5b2o11b2o6\$2ob2o6b2o12b2o6b2o\$2obo6b o2bo8bo2bo6bo2bo35bo3bo\$3bo7b2obo6bobobo7bobo34bobobobo\$3b2o9bo7bobo7b 2ob2o34b2ob2o\$14b2o7bo5\$15bo7bo7b2o\$4b2o8bobo5bobo6bobob2o37bo\$bo2bo9b 2o6b2obo7bobo34b2obobo\$obobo7b2o11bo7bobo34b2obo2bo\$o2bo7bobo8b3o9bo 39b2o\$b2o8b2o9bo6\$o2bo5bo2bo7b2ob2o6b2o3bo37b2o\$4o5b4o7b2obobo6bo2bobo 32b2obo2bo\$23bobo6bobo2bo32b2obo2bo\$4o7b4o8b2o8bo3b2o35b2o\$o2bo7bo2bo 5\$2ob2o7bo4bo7b2obo8b2ob2o29b2ob2o\$bobobo5bobo2bobo5bo2b2o9bobobobo25b obobobo\$o2bobo6b2o3bo6b2o3b2o7bo4b2o26bo3bobo\$2o2bo9b3o12bobo5b2o37b2o \$14bo15bo4\$b2o7b2o\$o2bo5bo2bo9b2o54b2o\$b3o6b3o8bob3o6b2ob2ob2o30b2o6bo \$21bo4bo5bob2ob2o2bo28bobobobobo\$b3o8b3o7b3obo13b2o31b2ob2o\$o2bo8bo2bo 8b2o\$b2o10b2o5\$2o2b2ob2o6b2o3bo3b2o5bob2ob2obo31bo6b2o\$o2bob2o2bo5bobo bobobobo5b2obobob2o30bobob2obobo\$b2o5b2o8b2ob2o11bo36b2ob2ob2o\$34b2o6\$ b2ob2o6b2ob2ob2o6b2o3b2o37b2o\$obobobo6bob2obo6bo2bobo2bo36bo5b2ob2o\$ob obobo6bo4bo7bobobobo39bobo2b2obo\$b2ob2o6b2o4b2o7b2ob2o39b2ob2o6\$2bo3bo 7b2obo8b2obobo41bob2o\$bobobobo6bob4o7bob2obo38b3ob2o\$bobobobo12bo5bo5b o37bo\$2obobob2o5bob4o6bob2obo39b3ob2o\$4bo9b2obo9bob2o42bob2o6\$27b2o42b 2obo\$2o3b2o6b2obo9bo2bob2o39bob3o\$obobobo5bobob3o6bobobob2o38bo5bo\$2bo bo7bo6bo5bobobo40bo5bo\$obobobo6b3obobo6bo2bo41b3obo\$2o3b2o8bob2o8b2o 44bob2o5\$b2ob2o9bo13b2ob2o3b2o34bobo\$obobobo7bobob2o9b2obo5bo32b3ob3o\$ o3bo2bo6bobobobob2o8bo4bo32bo7bo\$b3obobo5b2obobob2obo8bobobo34b3ob2obo \$3bob2o10bo13b2ob2o37bobobo5\$2obob2o5bo2bo2bo5bo2b2o\$ob3obo5b7o5b4obob 2o37b2o\$29bobo38bobob2ob2ob2o\$ob3obo5b7o7b2obobo39b2ob2ob2obobo\$2obob 2o5bo2bo2bo7b2ob2o50b2o6\$2obob2o9b2ob2o13bobo36bobob2o\$bob2obo8bobobob o10b3ob3o32b3ob2obo\$bo4bob2o6bo2bobo2b2o5bo7bo30bo\$2b3obo2bo9bobobobo 5bob2ob2obo31b3ob2obo\$4bob2o12b2ob2o7bobobobo34bobob2o\$35bo5\$bo3bo10b 2ob2o8b2o3b2o34b2obob2o\$obobobob2o6b2obo2bo5bo2bobo2bo33bob2ob2o\$obobo bobobo8bob2o5b2obobob2o\$b2obobobobo5b2obo11bobo37b3ob2o\$5bo3bo6bo2bob 2o8bobo36bo2bobobo\$18b2ob2o7b2ob2o36b2o3bo5\$4b2o11b2ob2o9b2o3bo36bo\$3b o2bob2o6bobobobo7bo2bobobo34bobo\$3b2obobobo5bo5bo7b2obob2o35bobo3bo\$2o bo2bobobo6b5o9bobo37b2ob2obobo\$2obobo3bo18b3o2bo44bo\$4bo12b2ob2o6bo4bo bo34bob2ob3o\$17b2ob2o12b2o34b2obobo! #C [[ GRID THEME BOOK ]]```
###### Figure 2.4(a): Triple pseudo still life

A 32-cell still life found in 2001 that can be broken down into three stable pieces, but not two.

RLE code: Select all
```x = 10, y = 8, rule = B3/S23 4bobob2o\$2b3ob2obo\$bo\$2bob2ob2o\$b2ob2obo\$8bo\$ob2ob3o\$2obobo! #C [[ GRID THEME BOOK ]]```
###### Figure 2.4(b): Quad pseudo still life

A 34-cell pseudo still life that can be decomposed into four stable subpatterns, but can not be decomposed into two or three stable subpatterns.

RLE code: Select all
```x = 11, y = 9, rule = B3/S23 8b2ob\$3b2obo2bob\$3bob2obo2b\$8b2ob\$3bob2o3bo\$b3ob2ob2ob\$o7bo2b\$b3ob2obo 2b\$3bobobo! #C [[ GRID THEME BOOK ]]```
###### Figure 2.5: messy pseudo still life

A complicated pseudo still life.

RLE code: Select all
```x = 16, y = 21, rule = B3/S23 7bob2ob2o\$5b3ob2obobo\$4bo9bo\$4b2ob2ob2o2b2o\$8bob2o\$4b2obo\$4b2ob2ob2o\$ 8bob2o\$4b2obo\$4b2ob2ob2o\$8bob2o\$4b2obo\$4b2ob2ob2o\$11bo\$4b2ob2obo\$4bo3b ob2o\$5bobo\$2o2b2ob2ob2o\$bo9bo\$bobob2ob3o\$2b2ob2obo! #C [[ GRID THEME BOOK ]]```
###### Figure 2.6: tub boat ship

The tub, boat, and ship all belong to simple infinite families of still lifes.

RLE code: Select all
```x = 33, y = 28, rule = B3/S23 31bo\$10bo9bo9bobo\$bo7bobo7bobo7bobo\$obo5bobo7bobo7bobo\$bo7bo7bobo7bobo \$18bo9bo6\$31bo\$10bo9bo9bobo\$bo7bobo7bobo7bobo\$obo5bobo7bobo7bobo\$2o6b 2o7bobo7bobo\$17b2o8b2o6\$31b2o\$10b2o8b2o8bobo\$b2o6bobo7bobo7bobo\$obo5bo bo7bobo7bobo\$2o6b2o7bobo7bobo\$17b2o8b2o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.7: snake canoe

The snake and canoe all belong to simple infinite families of still lifes.

RLE code: Select all
```x = 79, y = 6, rule = B3/S23 2obo5b2o8b2o9b2o14b2o6b2o7b2o8b2o\$ob2o5bobobo5bobo8bobo13bobo5bobo6bob o7bobo\$12b2o8bobo8bo13b2o8bo8bo9bo\$23b2o9bobo19b2o9bo9bo\$35b2o29b2o10b o\$77b2o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.9: hook tail examples

Several still lifes that use hooks and/or tails to stabilize their ends.

RLE code: Select all
```x = 54, y = 5, rule = B3/S23 2o8b2o9bo8bo8b2o8b2o\$obo6bo2bo7bobo6bobo7bobo7bobo\$2bo7bobo7bobo7bobo 7bobo8bo\$2b2o5b2ob2o5b2ob2o8bo9bo8bobo\$32b2o8b2o8b2o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.11: still life path

An example of how an arbitrarily-drawn path of live cells can be stabilized to be part of a still life.

RLE code: Select all
```x = 24, y = 10, rule = B3/S23 13b2o7b2o\$o12bobo3b2o2bo\$bo12bobo2b2obo\$2bo12bo6b2o\$3b5o8b5o\$7bo12bob 2o\$7bo6b5obob2o\$6bo7bo4bo\$5bo9bo2bo\$5bo8b2o2b2o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.12: 5 cell induction

A row of 5 orthogonally-connected cells can be stabilized by a single cell, like one from a tub or an eater 1.

RLE code: Select all
```x = 12, y = 7, rule = B3/S23 2o4bo\$obo2bobo\$2bo2bobo2bo\$2b2obobobobo\$5bobo2bo\$5bobo\$6bo! #C [[ GRID THEME BOOK ]]```
###### Figure 2.13: induction coil examples

A pattern that demonstrates many induction coils.

RLE code: Select all
```x = 31, y = 11, rule = B3/S23 27b2o\$3b2obo2b2o2b2obob2ob2obobo2bo\$3bob2o2b2o2bob2ob2obob2ob4o2\$b29o\$ o29bo\$b29o2\$b2ob2ob2obo2b4ob7o2b3o\$bob2ob2ob2o2bo2bobo2bo2bo2bo2bo\$29b 2o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.14: eater 1 glider

An eater 1 about to eat a glider.

RLE code: Select all
```x = 8, y = 7, rule = B3/S23 2bo\$obo\$b2o\$4b2o\$4bobo\$6bo\$6b2o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.15: eater 1 multi

Eater 1 about to eat a glider, a middleweight spaceship, a lightweight spaceship, and several other objects.

RLE code: Select all
```x = 78, y = 8, rule = B3/S23 71bo\$2bo9b4o8b5o9b2o10bo9bo9bobo\$obo8bo3bo7bo4bo9b2o10bo8bobo8bobo\$b2o 12bo12bo9b2o10bo7bo2bo9b2o\$4b2o5bo2bo2b2o4bo3bo2b2o9b2o9b2o5b2o2b2o9b 2o\$4bobo10bobo5bo4bobo8bobo8bobo8bobo8bobo\$6bo12bo12bo10bo10bo10bo10bo \$6b2o11b2o11b2o9b2o9b2o9b2o9b2o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.16(a): Eater 2

A well-known eater and 19-cell still life that can eat gliders that approach it along four different paths.

RLE code: Select all
```x = 35, y = 33, rule = B3/S23 2bo\$obo\$b2o\$6bo\$4bobo\$5b2o\$10bo\$8bobo\$9b2o\$14bo\$12bobo\$13b2o15\$28b2obo \$28b2ob3o\$34bo\$28b2ob3o\$29bobo\$29bobo\$30bo! #C [[ GRID THEME BOOK ]]```
###### Figure 2.16(b): Eater 5

A 12-cell still life and eater composed of a tub with tail and a block that is capable of eating gliders that approach from the top-right.

RLE code: Select all
```x = 12, y = 13, rule = B3/S23 2bo\$obo\$b2o2\$5bo\$5bobo\$5b2o\$10b2o\$6bo3b2o\$5bobo\$4bobo\$4bo\$3b2o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.17: Boat-bit

A reaction that shows how a snake can be used to eat two gliders. Later in the book, we will use this reaction to store data in memory.

RLE code: Select all
```x = 20, y = 15, rule = B3/S23 2bo\$obo\$b2o7\$11bo\$9bobo\$10b2o2\$16bob2o\$16b2obo! #C [[ GRID THEME BOOK ]]```
###### Figure 2.18: glider loaf flip

A glider flips a loaf, and then is flipped back by another glider.

RLE code: Select all
```x = 11, y = 11, rule = B3/S23 bo\$2bo\$3o\$4b2o\$3bo2bo\$3bobo\$4bo2\$8b3o\$8bo\$9bo! #C [[ GRID THEME BOOK ]]```
###### Figure 2.19: Eater 3

A 31-cell still life and symmetric eater.

RLE code: Select all
```x = 12, y = 12, rule = B3/S23 b2o\$o2bo2b2o\$obo4bo2bo\$bo5bobobo\$4b2obo2bo\$4bo2bo\$bo4bo\$b5o2\$3bo\$2bobo \$3bo! #C [[ GRID THEME BOOK ]]```
###### Figure 2.20: glider block move

A glider moves a block, and then it is moved back by another glider.

RLE code: Select all
```x = 13, y = 4, rule = B3/S23 4b2o\$o3b2o5bo\$b2o7b2o\$2o8bobo! #C [[ GRID THEME BOOK ]]```
###### Figure 2.21: unstable eater 1s

Two eater 1s too close to each other, so they are no longer stable.

RLE code: Select all
```x = 21, y = 12, rule = B3/S23 2bo\$obo\$b2o15bo\$18bobo\$18b2o2\$7b2o\$7bobo\$9bo2b2o\$9b3obo\$11bo\$10b2o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.22: welded eater 1s

Two welded eater 1s eating two gliders.

RLE code: Select all
```x = 21, y = 13, rule = B3/S23 2bo\$obo\$b2o15bo\$18bobo\$18b2o2\$7b2o\$7bobo\$9bo2b2o\$9bobobo\$6b2obobo\$6b2o bobo\$10bo! #C [[ GRID THEME BOOK ]]```
###### Figure 2.24(a): eater constrained eater 5 b

An "almost" eater that isn't quite stable.

RLE code: Select all
```x = 10, y = 7, rule = B3/S23 2ob2o2b3o\$bobobobo\$bo2bo3bo\$bo\$2bo\$3bobo\$4b2o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.24(b): eater constrained done

An eater that eats a glider at its corner.

RLE code: Select all
```x = 13, y = 7, rule = B3/S23 3b2ob2o2b3o\$2bobobobobo\$2bobo2bo3bo\$b2obo\$o3b2o\$bobo2bobo\$2ob2o2b2o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.25(a): Zebra stripes

An infinite still life with density 1/2.

RLE code: Select all
```x = 72, y = 47, rule = B3/S23:T72,48 72o2\$72o2\$72o2\$72o2\$72o2\$72o2\$72o2\$72o2\$72o2\$72o2\$72o2\$72o2\$72o2\$72o2\$ 72o2\$72o2\$72o2\$72o2\$72o2\$72o2\$72o2\$72o2\$72o2\$72o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.25(b): Chicken wire

An infinite still life with density 1/2.

RLE code: Select all
```x = 72, y = 48, rule = B3/S23:T72,48 5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b 5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$ 5b5o2b3o2b2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b 2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o 5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o 2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b 5o2b3o2b2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o 3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b 2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b 3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o 2b3o2b2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b 2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o 3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b3o 2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b 3o2b2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o 2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b 2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b3o2b 2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o 2b2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b 2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o 2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b3o2b2o 2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b 2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o 2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b 2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b3o2b2o2b 2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o 2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b 4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o 2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b3o2b2o2b2o 4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o3b5o4b2o\$5b5o2b3o2b2o2b 2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o\$5o5b2o3b2o2b2o2b4o3b6o5b2o3b2o2b2o2b4o 3b5o4b2o\$5b5o2b3o2b2o2b2o4b3o6b5o2b3o2b2o2b2o4b3o5b4o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.25(c): Onion rings

An infinite still life with density 1/2.

RLE code: Select all
```x = 72, y = 48, rule = B3/S23:T72,48 6b6o6b6o6b6o6b6o6b6o6b6o\$b4obo4bob4obo4bob4obo4bob4obo4bob4obo4bob4obo 4bo\$bo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bob ob2obo\$bo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obobo 2bobob2obo\$b4obo4bob4obo4bob4obo4bob4obo4bob4obo4bob4obo4bo\$6b6o6b6o6b 6o6b6o6b6o6b6o\$6o6b6o6b6o6b6o6b6o6b6o\$o4bob4obo4bob4obo4bob4obo4bob4ob o4bob4obo4bob4o\$ob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obo bo2bobob2obobo2bo\$ob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2o bobo2bobob2obobo2bo\$o4bob4obo4bob4obo4bob4obo4bob4obo4bob4obo4bob4o\$6o 6b6o6b6o6b6o6b6o6b6o\$6b6o6b6o6b6o6b6o6b6o6b6o\$b4obo4bob4obo4bob4obo4bo b4obo4bob4obo4bob4obo4bo\$bo2bobob2obobo2bobob2obobo2bobob2obobo2bobob 2obobo2bobob2obobo2bobob2obo\$bo2bobob2obobo2bobob2obobo2bobob2obobo2bo bob2obobo2bobob2obobo2bobob2obo\$b4obo4bob4obo4bob4obo4bob4obo4bob4obo 4bob4obo4bo\$6b6o6b6o6b6o6b6o6b6o6b6o\$6o6b6o6b6o6b6o6b6o6b6o\$o4bob4obo 4bob4obo4bob4obo4bob4obo4bob4obo4bob4o\$ob2obobo2bobob2obobo2bobob2obob o2bobob2obobo2bobob2obobo2bobob2obobo2bo\$ob2obobo2bobob2obobo2bobob2ob obo2bobob2obobo2bobob2obobo2bobob2obobo2bo\$o4bob4obo4bob4obo4bob4obo4b ob4obo4bob4obo4bob4o\$6o6b6o6b6o6b6o6b6o6b6o\$6b6o6b6o6b6o6b6o6b6o6b6o\$b 4obo4bob4obo4bob4obo4bob4obo4bob4obo4bob4obo4bo\$bo2bobob2obobo2bobob2o bobo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obo\$bo2bobob2obobo2bobo b2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obo\$b4obo4bob4obo4bo b4obo4bob4obo4bob4obo4bob4obo4bo\$6b6o6b6o6b6o6b6o6b6o6b6o\$6o6b6o6b6o6b 6o6b6o6b6o\$o4bob4obo4bob4obo4bob4obo4bob4obo4bob4obo4bob4o\$ob2obobo2bo bob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bo\$ob2obobo 2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bo\$o4bob 4obo4bob4obo4bob4obo4bob4obo4bob4obo4bob4o\$6o6b6o6b6o6b6o6b6o6b6o\$6b6o 6b6o6b6o6b6o6b6o6b6o\$b4obo4bob4obo4bob4obo4bob4obo4bob4obo4bob4obo4bo\$ bo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2o bo\$bo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bobo b2obo\$b4obo4bob4obo4bob4obo4bob4obo4bob4obo4bob4obo4bo\$6b6o6b6o6b6o6b 6o6b6o6b6o\$6o6b6o6b6o6b6o6b6o6b6o\$o4bob4obo4bob4obo4bob4obo4bob4obo4bo b4obo4bob4o\$ob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2b obob2obobo2bo\$ob2obobo2bobob2obobo2bobob2obobo2bobob2obobo2bobob2obobo 2bobob2obobo2bo\$o4bob4obo4bob4obo4bob4obo4bob4obo4bob4obo4bob4o\$6o6b6o 6b6o6b6o6b6o6b6o! #C [[ GRID THEME BOOK ]]```
###### Table 2.2(2): densest block

A block is the densest 2x2 still life.

RLE code: Select all
```x = 2, y = 2, rule = B3/S23 2o\$2o! #C [[ GRID THEME BOOK ]]```
###### Table 2.2(3): densest ship

A ship is the densest 3x3 still life.

RLE code: Select all
```x = 3, y = 3, rule = B3/S23 2o\$obo\$b2o! #C [[ GRID THEME BOOK ]]```
###### Table 2.2(4): densest pond

A pond is the densest 4x4 still life.

RLE code: Select all
```x = 4, y = 4, rule = B3/S23 b2o\$o2bo\$o2bo\$b2o! #C [[ GRID THEME BOOK ]]```
###### Table 2.2(5): densest four blocks

The densest 5x5 still life.

RLE code: Select all
```x = 5, y = 5, rule = B3/S23 2ob2o\$2ob2o2\$2ob2o\$2ob2o! #C [[ GRID THEME BOOK ]]```
###### Table 2.2(6): densest 6

The densest 6x6 still life.

RLE code: Select all
```x = 6, y = 6, rule = B3/S23 2ob2o\$2ob2o2\$2ob2o\$2obobo\$4b2o! #C [[ GRID THEME BOOK ]]```
###### Table 2.2(7): densest 7

The densest 7x7 still life.

RLE code: Select all
```x = 7, y = 7, rule = B3/S23 2ob2obo\$bobob2o\$o2bo\$3ob3o\$3bo2bo\$2obobo\$ob2ob2o! #C [[ GRID THEME BOOK ]]```
###### Table 2.2(8): densest 8

The densest 8x8 still life.

RLE code: Select all
```x = 8, y = 8, rule = B3/S23 2ob2ob2o\$2ob2ob2o2\$2ob2ob2o\$2ob2ob2o2\$2ob2ob2o\$2ob2ob2o! #C [[ GRID THEME BOOK ]]```
###### Table 2.2(9): densest 9

The densest 9x9 still life.

RLE code: Select all
```x = 9, y = 9, rule = B3/S23 2obobob2o\$ob2ob2obo2\$b7o\$o7bo\$4ob4o\$3bobo\$2obobob2o\$ob2ob2obo! #C [[ GRID THEME BOOK ]]```
###### Table 2.2(10): densest 10

The densest 10x10 still life.

RLE code: Select all
```x = 10, y = 10, rule = B3/S23 ob2ob2ob2o\$2ob2obob2o\$6bo\$2ob3ob3o\$bobo2bo2bo\$o2bo2bobo\$3ob3ob2o\$3bo\$ 2obob2ob2o\$2ob2ob2obo! #C [[ GRID THEME BOOK ]]```
###### Figure 2.30: dense oscillator

A period 6 infinite oscillator that has density 3/4 in two of its phases.

RLE code: Select all
```x = 72, y = 48, rule = B3/S23:T72,48 72o\$72o3\$72o\$72o\$72o\$72o\$72o\$72o3\$72o\$72o\$72o\$72o\$72o\$72o3\$72o\$72o\$72o \$72o\$72o\$72o3\$72o\$72o\$72o\$72o\$72o\$72o3\$72o\$72o\$72o\$72o\$72o\$72o3\$72o\$ 72o\$72o\$72o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.33: two tables on block

A 16-cell strict still life that would never be found by a greedy strict still life search.

RLE code: Select all
```x = 8, y = 4, rule = B3/S23 2ob2ob2o\$bob2obo\$bo4bo\$2o4b2o! #C [[ GRID THEME BOOK ]]```
###### Figure 2.34: sl hard to find

Two strict still lifes that are hard to find with search software.

RLE code: Select all
```x = 32, y = 8, rule = B3/S23 2o\$obo2b2o14b2o7b2o\$2bo2bo15bo9bo\$2b2obo17bo5bo\$5bob2o13b2o2bo2b2o\$5bo 2bo14bobobobo\$4b2o2bobo12bo2bo2bo\$9b2o11b2o5b2o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.1(a): strict pseudo 1

A still life.

RLE code: Select all
```x = 6, y = 6, rule = B3/S23 bo\$obo\$b2o\$3b2o\$3bobo\$4bo! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.1(b): strict pseudo 4

A still life.

RLE code: Select all
```x = 10, y = 9, rule = B3/S23 5bo\$bo2bobo\$b4ob3o\$9bo\$3bob2obo\$b3ob2ob2o\$o8bo\$b3ob2obo\$3bob2ob2o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.1(c): strict pseudo 2

A still life.

RLE code: Select all
```x = 7, y = 4, rule = B3/S23 bo\$obob2o\$b2obobo\$5bo! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.1(d): strict pseudo 5

A still life.

RLE code: Select all
```x = 9, y = 9, rule = B3/S23 4bo\$2obobo\$ob2ob3o\$8bo\$b2ob2obo\$b2ob2ob2o\$8bo\$b2ob2obo\$b2ob2ob2o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.1(e): strict pseudo 3

A still life.

RLE code: Select all
```x = 7, y = 7, rule = B3/S23 bo\$obo\$b2o2\$4b2o\$4bobo\$5bo! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.1(f): strict pseudo 6

A still life.

RLE code: Select all
```x = 9, y = 7, rule = B3/S23 2o5b2o\$o2bobo2bo\$b3ob3o2\$3b3o\$2bo3bo\$2b2ob2o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.3(a): pseudo 1

A pseudo still life.

RLE code: Select all
```x = 5, y = 7, rule = B3/S23 2bo\$bobo\$bobo\$2ob2o2\$2ob2o\$2ob2o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.3(b): pseudo 4

A pseudo still life.

RLE code: Select all
```x = 9, y = 8, rule = B3/S23 4bo\$2obobo\$ob2ob3o\$8bo\$b2ob2ob2o\$bo3bobo\$2bobo3bo\$b2ob2ob2o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.3(c): pseudo 2

A pseudo still life.

RLE code: Select all
```x = 8, y = 7, rule = B3/S23 2bo\$bobo\$bobo\$2ob2ob2o\$7bo\$2ob2obo\$2ob2ob2o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.3(d): pseudo 5

A pseudo still life.

RLE code: Select all
```x = 11, y = 13, rule = B3/S23 4bo\$2obobo\$ob2ob3o\$8bo\$b2ob2ob2o\$bo3bobo\$2bobo3bo\$b2ob2ob2o\$bo\$2bob2ob 2o\$b2obob2obo\$9bo\$9b2o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.3(e): pseudo 3

A pseudo still life.

RLE code: Select all
```x = 8, y = 10, rule = B3/S23 2bo\$bobo\$bobo\$2ob2ob2o\$7bo\$2ob2obo\$2ob2ob2o\$7bo\$2ob2obo\$2ob2ob2o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.3(f): pseudo 6

A pseudo still life.

RLE code: Select all
```x = 14, y = 9, rule = B3/S23 2b2ob2ob2o\$bobob2ob2o\$bo\$2o2b2ob2obo\$o3b2ob2ob3o\$bo11bo\$2bo9b2o\$3bob2o b2obo\$4b2ob2ob2o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.4(a): path 1

A path of live cells that can be stabilized into a still life by making some other cells alive.

RLE code: Select all
```x = 6, y = 4, rule = B3/S23 b4o\$o4bo\$o4bo\$o4bo! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.4(b): path 3

A path of live cells that can be stabilized into a still life by making some other cells alive.

RLE code: Select all
```x = 9, y = 4, rule = B3/S23 b5o\$o5bo\$o6bo\$o7bo! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.4(c): path 2

A path of live cells that can be stabilized into a still life by making some other cells alive.

RLE code: Select all
```x = 6, y = 5, rule = B3/S23 b4o\$o4bo\$o4bo\$o4bo\$bo2bo! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.7(a): induction coil 1

An object that can be stabilized with induction coils.

RLE code: Select all
```x = 12, y = 4, rule = B3/S23 b10o\$obo3bo4bo\$o3bo3bo2bo\$b10o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.7(b): induction coil 3

An object that can be stabilized with induction coils.

RLE code: Select all
```x = 13, y = 9, rule = B3/S23 b11o\$obo3bo3bobo\$o3bo3bo3bo\$b9o2bo\$10bobo\$10bobo\$10bobo\$10bobo\$11bo! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.7(c): induction coil 2

An object that can be stabilized with induction coils.

RLE code: Select all
```x = 12, y = 5, rule = B3/S23 6bo\$b5ob4o\$obo3bo4bo\$o3bo3bo2bo\$b10o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.9(a): weld 1

Two gliders to be destroyed by an eater.

RLE code: Select all
```x = 13, y = 11, rule = B3/S23 2bo\$obo\$b2o6\$10b2o\$10bobo\$10bo! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.9(b): weld 2

Two gliders to be destroyed by an eater.

RLE code: Select all
```x = 13, y = 12, rule = B3/S23 2bo\$obo\$b2o7\$10b2o\$10bobo\$10bo! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.9(c): weld 5

Four gliders that we would like to eat.

RLE code: Select all
```x = 19, y = 19, rule = B3/S23 12bo\$11bo\$11b3o3\$2bo\$obo\$b2o4\$16b2o\$16bobo\$16bo3\$5b3o\$7bo\$6bo! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.9(d): weld 3

Two gliders to be destroyed by an eater.

RLE code: Select all
```x = 13, y = 13, rule = B3/S23 2bo\$obo\$b2o8\$10b2o\$10bobo\$10bo! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.9(e): weld 4

An arrangement of 4 gliders that we would like to eat.

RLE code: Select all
```x = 15, y = 12, rule = B3/S23 2bo\$obo\$b2o\$6bo\$4bobo\$5b2o\$10bo\$8bobo\$9b2o\$14bo\$12bobo\$13b2o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.9(f): weld 6

Several gliders that we would like to eat.

RLE code: Select all
```x = 40, y = 40, rule = B3/S23 36bo\$35bo\$2bo32b3o\$obo\$b2o30bo\$6bo25bo\$4bobo25b3o\$5b2o\$10bo19bo\$8bobo 18bo\$9b2o18b3o\$14bo\$12bobo12bo\$13b2o11bo\$26b3o11\$11b3o\$13bo11b2o\$12bo 12bobo\$25bo\$8b3o18b2o\$10bo18bobo\$9bo19bo\$33b2o\$5b3o25bobo\$7bo25bo\$6bo 30b2o\$37bobo\$2b3o32bo\$4bo\$3bo! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.12: still life impossible

A collection of live cells that cannot be extended to a still life.

RLE code: Select all
```x = 6, y = 2, rule = B3/S23 2o2b2o\$ob2obo! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.13(a): fast glider eater

A still life that can eat a glider.

RLE code: Select all
```x = 6, y = 8, rule = B3/S23 3b2o\$2bobo\$3bo2\$b5o\$2bo2bo\$o\$2o! #C [[ GRID THEME BOOK ]]```
###### Exercise 2.13(b): fast glider eater b

A still life that can eat a glider.

RLE code: Select all
```x = 8, y = 7, rule = B3/S23 3b2o\$4bo\$4bob2o\$b2ob2obo\$2bo\$obo\$2o! #C [[ GRID THEME BOOK ]]```
###### Solution 2.4(a): path 1

A still life.

RLE code: Select all
```x = 8, y = 7, rule = B3/S23 2b2o\$2b2o2\$2b4o\$bo4bo\$bob2obo\$2ob2ob2o! #C [[ GRID THEME BOOK ]]```
###### Solution 2.4(b): path 3

A still life.

RLE code: Select all
```x = 12, y = 10, rule = B3/S23 5b2o\$b2o2bo2b2o\$bo4bob2o\$2b5o\$8b2o\$2b6obo\$bo5bo\$bob2o3bo\$2ob2o4bobo\$ 10b2o! #C [[ GRID THEME BOOK ]]```
###### Solution 2.4(c): path 2

A still life.

RLE code: Select all
```x = 14, y = 11, rule = B3/S23 7b2o\$7b2o2\$bo3b4o\$obobo2bobob2o\$obobo4bobobo\$b2obobo2bobobo\$5b4o3bo2\$ 5b2o\$5b2o! #C [[ GRID THEME BOOK ]]```
###### Solution 2.7(a): induction coil 1

A still life stabilized by some induction coils.

RLE code: Select all
```x = 12, y = 12, rule = B3/S23 2o8b2o\$o3bo2bo3bo\$b10o2\$b10o\$obo3bo4bo\$o3bo3bo2bo\$b10o2\$b2ob2o2b3o\$b2o b2o2bo2bo\$9b2o! #C [[ GRID THEME BOOK ]]```
###### Solution 2.7(b): induction coil 3

A still life stabilized by some induction coils.

RLE code: Select all
```x = 16, y = 17, rule = B3/S23 b2ob2ob2ob2o\$b2ob2ob2ob2o2\$b11o\$obo3bo3bobob2o\$o3bo3bo3bob2o\$b9o2bo\$ 10bobob2o\$b8obobo2bo\$o7bobobobo\$2ob2obobobobob2o\$bob2ob2o3bo\$o\$2ob2ob 2o\$4bobo\$4bobo\$5bo! #C [[ GRID THEME BOOK ]]```
###### Solution 2.7(c): induction coil 2

A still life stabilized by some induction coils.

RLE code: Select all
```x = 12, y = 14, rule = B3/S23 6bo\$5bobo\$6bo\$2o8b2o\$o3b5o2bo\$b4o3b3o\$6bo\$b5ob4o\$obo3bo4bo\$o3bo3bo2bo\$ b10o2\$b2o2b2o2b2o\$b2o2b2o2b2o! #C [[ GRID THEME BOOK ]]```
###### Solution 2.9(a): weld 1

A way of welding two eater 1s.

RLE code: Select all
```x = 19, y = 17, rule = B3/S23 3\$5bo\$3bobo\$4b2o\$7b2o\$7bobo\$9bo\$9bobo\$10b2o\$13b2o\$13bobo\$13bo! #C [[ GRID THEME BOOK ]]```
###### Solution 2.9(b): weld 2

A way of welding two eater 1s.

RLE code: Select all
```x = 13, y = 12, rule = B3/S23 2bo\$obo6bo\$b2o5bobo\$4b2o2bobo\$4bobob2o\$6bo\$6bo\$3b2obobo\$2bobo2b2o\$2bob o5b2o\$3bo6bobo\$10bo! #C [[ GRID THEME BOOK ]]```
###### Solution 2.9(c): weld 5

An eater eating 4 gliders.

RLE code: Select all
```x = 19, y = 19, rule = B3/S23 12bo\$11bo\$11b3o2\$9b2o\$2bo7bo\$obo4b3o\$b2o4bo2b3o\$4b2obobo2bo\$4bobobobob obo\$6bo2bobob2o\$6b3o2bo4b2o\$9b3o4bobo\$8bo7bo\$8b2o2\$5b3o\$7bo\$6bo! #C [[ GRID THEME BOOK ]]```
###### Solution 2.9(d): weld 3

An eater destroying two gliders.

RLE code: Select all
```x = 13, y = 13, rule = B3/S23 2bo\$obo\$b2o\$4b2o\$4bobob2o\$6bob2o\$6bo\$3b2obo\$3b2obobo\$7b2o\$10b2o\$10bobo \$10bo! #C [[ GRID THEME BOOK ]]```
###### Solution 2.9(e): weld 4

An eater 2 variant that sometimes can be used to construct patterns with smaller bounding boxes.

RLE code: Select all
```x = 21, y = 20, rule = B3/S23 2bo\$obo\$b2o\$6bo\$4bobo\$5b2o\$10bo\$8bobo\$9b2o\$14bo\$12bobo\$13b2o4b2o\$20bo\$ 15b2obo\$15b2ob2o2\$15b2ob2o\$16bobo\$16bobo\$17bo! #C [[ GRID THEME BOOK ]]```
###### Solution 2.9(f): weld 6

An eater destroying numerous gliders.

RLE code: Select all
```x = 40, y = 40, rule = B3/S23 36bo\$35bo\$2bo32b3o\$obo\$b2o30bo\$6bo25bo\$4bobo25b3o\$5b2o\$10bo19bo\$8bobo 18bo\$9b2o18b3o\$14bo\$12bobo12bo\$13b2o11bo\$26b3o\$15b2obo2bob2o\$15b2ob4ob 2o2\$15b2ob4ob2o\$16bobo2bobo\$16bobo2bobo\$15b2ob4ob2o2\$15b2ob4ob2o\$15b2o bo2bob2o\$11b3o\$13bo11b2o\$12bo12bobo\$25bo\$8b3o18b2o\$10bo18bobo\$9bo19bo\$ 33b2o\$5b3o25bobo\$7bo25bo\$6bo30b2o\$37bobo\$2b3o32bo\$4bo\$3bo! #C [[ GRID THEME BOOK ]]```
###### Solution 2.13(a): fast glider eater

A fast-recovering glider eater.

RLE code: Select all
```x = 8, y = 9, rule = B3/S23 bo\$2bo2b2o\$3obobo\$5bo2\$3b5o\$4bo2bo\$2bo\$2b2o! #C [[ GRID THEME BOOK ]]```
###### Solution 2.13(b): fast glider eater b

A fast-recovering glider eater.

RLE code: Select all
```x = 10, y = 8, rule = B3/S23 bo\$2bo2b2o\$3o3bo\$6bob2o\$3b2ob2obo\$4bo\$2bobo\$2b2o! #C [[ GRID THEME BOOK ]]```
###### Solution 2.15: incomplete glider eater

A compact glider eater.

RLE code: Select all
```x = 10, y = 7, rule = B3/S23 bo6b2o\$2bo2b2o2bo\$3o3bobo\$6bob2o\$3b2obo\$3bo2bo\$4b2o! #C [[ GRID THEME BOOK ]]```