A268791 Number of n X n 0..2 arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two exactly once.

0, 22, 248, 4800, 168740, 11138352, 1384570516, 325815151556, 145913571668076, 124768928833331732, 204377241703937153076, 642788798787566885184552, 3889478620658657294120765368, 45350632160719542617837369658508

Offset

1,2

Comments

Diagonal of A268798.

Links

R. H. Hardin, Table of n, a(n) for n = 1..18

Example

Some solutions for n=4
..1..0..0..0. .2..1..2..1. .2..2..1..0. .1..2..1..2. .2..2..2..1
..1..0..1..0. .2..2..2..2. .1..0..0..0. .2..2..2..2. .2..1..2..2
..0..0..0..0. .2..2..2..2. .0..1..0..1. .2..1..2..1. .2..2..2..1
..1..0..0..0. .1..2..1..1. .0..0..0..0. .2..1..2..2. .2..2..2..1

Crossrefs

Cf. A268798.

Sequence in context: A200206 A252819 A109251 * A161521 A161900 A162364

Adjacent sequences: A268788 A268789 A268790 * A268792 A268793 A268794

Keyword

nonn

Author

R. H. Hardin, Feb 13 2016

Status

approved