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A330283
Number of n-celled quasi still lifes in Conway's Game of Life, up to rotation and reflection.
2
0, 0, 0, 0, 0, 0, 0, 6, 13, 57, 141, 465, 1224, 3956, 11599, 36538, 107415, 327250, 972040, 2957488, 8879327, 26943317
OFFSET
1,8
COMMENTS
A quasi still life is a still life made up of two or more strict still lifes (A019473) that share at least 1 neighboring dead cell, but those cells still remain dead due to underpopulation just like if we were to separate those component strict still lifes. Contrast with pseudo still lifes (A056613), where the component strict still lifes share at least 1 neighboring dead cell that remains dead, but the reason shifts from underpopulation in the strict still lifes to overpopulation in the combined pattern.
EXAMPLE
When n = 8, the 6 quasi still lifes are the various arrangements of blocks and tubs in which they share a neighbor, but that neighbor remains dead due to underpopulation. In the diagrams below, "." is a dead cell, "o" is a live cell, and "*" is a dead neighboring cell that makes the pattern a quasi still life:
.o...o.
o.o*o.o
.o...o.
.
.o.....
o.o*.o.
.o.*o.o
.....o.
.
oo...
oo...
..*..
...oo
...oo
.
oo....
oo....
..*.o.
...o.o
....o.
.
.o.....
o.o....
.o.*.o.
....o.o
.....o.
.
.o....
o.o...
.o.*..
..*.o.
...o.o
....o.
CROSSREFS
Sequence in context: A296619 A064521 A367663 * A361244 A374348 A262238
KEYWORD
nonn,hard,more
AUTHOR
Nathaniel Johnston, Dec 09 2019
STATUS
approved