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:natural Occurring often in random patterns. There is no precise measure of naturalness, since the most useful definition of "random" in this context is open to debate. Nonetheless, it is clear that objects such as blocks, blinkers, beehives and gliders are very natural, while eater2s, darts, guns, etc., are not.

:negentropy (p2) Compare Hertz oscillator.

	...OO.O....
	...O.OO....
	...........
	....OOO....
	...O.O.O.OO
	...OO..O.OO
	OO.O...O...
	OO.O...O...
	....OOO....
	...........
	....OO.O...
	....O.OO...

:neighbour Any of the eight cells adjacent to a given cell. A cell is therefore not considered to be a neighbour of itself, although the neighbourhood used in Life does in fact include this cell (see cellular automaton).

:new five (p3) Found by Dean Hickerson, January 1990.

	..OO.....
	.O..O....
	.O.O..O..
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	O........
	.OOO.OOOO
	.....O..O
	O.OO.....
	OO.OO....

:new gun An old name for the second known basic gun (found, like the first, by Bill Gosper), shown below. A number of other ways of constructing a gun from two twin bees shuttles have since been found - see edge shooter for one of these.

	.........................OO.....OO
	.........................OO.....OO
	..................................
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	..................................
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	...........................OO.OO..
	..........................O.....O.
	..................................
	.........................O.......O
	.........................O..O.O..O
	.........................OOO...OOO
	..................................
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	.................O................
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	OO................OO..............
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	OO...............OO........OO.....
	.................O................

:Noah's ark The following diagonal puffer consisting of two switch engines. This was found by Charles Corderman in 1971. The name comes from the variety of objects it leaves behind: blocks, blinkers, beehives, loaves, gliders, ships, boats, long boats, beacons and block on tables.

	..........O.O..
	.........O.....
	..........O..O.
	............OOO
	...............
	...............
	...............
	...............
	...............
	.O.............
	O.O............
	...............
	O..O...........
	..OO...........
	...O...........

See also ark.

:n-omino Any polyomino with exactly n cells.

:non-monotonic A spaceship is said to be non-monotonic if its leading edge falls back in some generations. The first example (shown below) was found by Hartmut Holzwart in August 1992. This is p4 and travels at c/4. In April 1994, Holzwart found examples of p3 spaceships with this property, and this is clearly the smallest possible period. Another non-monotonic spaceship is the weekender.

	..........OO.O.......
	......OOO.O.OOO......
	..O.O..........O...OO
	OO....OO.....O...OOOO
	..O.OO..O....OOO.O...
	........O....O.......
	..O.OO..O....OOO.O...
	OO....OO.....O...OOOO
	..O.O..........O...OO
	......OOO.O.OOO......
	..........OO.O.......

:non-spark Something that looks like a spark, but isn't. An OWSS produces one of these instead of a belly spark, and is destroyed by it.

:non-standard spaceship Any spaceship other than a glider, LWSS, MWSS or HWSS.


Introduction | 1-9 | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Bibliography