A221307 - OEIS

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A221307

Number of nX5 arrays of occupancy after each element moves to some horizontal, vertical or antidiagonal neighbor, with every occupancy equal to zero or two

0, 90, 0, 38146, 0, 19642342, 0, 9842336697, 0, 4907450696408, 0, 2441328266555768, 0, 1213489893520857350, 0, 602992641919618581949, 0, 299597420150822374508346, 0, 148848899893861061853934856, 0

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

COMMENTS

Column 5 of A221308

LINKS

Table of n, a(n) for n=1..21.

EXAMPLE

Some solutions for n=4

..0..0..0..2..2....0..2..0..0..0....0..0..2..0..0....2..2..0..2..0

..2..2..0..0..0....0..2..0..2..0....2..2..2..2..0....0..0..0..2..2

..0..0..2..2..0....2..2..2..2..0....0..0..0..2..2....0..0..0..0..2