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A268988
Number of n X n binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two not more than once.
1
2, 13, 174, 6009, 421450, 66954420, 22995344760, 17373640598542, 29082748697180602, 107300241515211644436, 883523091936988991189604, 16140842052133986432421342048, 659806253617230823177640504040304
OFFSET
1,1
COMMENTS
Diagonal of A268995.
LINKS
EXAMPLE
Some solutions for n=4
..0..1..0..1. .0..0..1..0. .1..1..0..1. .0..0..0..1. .0..0..0..0
..0..1..0..0. .0..0..0..0. .0..1..0..0. .0..1..0..0. .0..0..1..0
..0..0..1..1. .1..0..0..0. .0..0..1..0. .0..0..0..1. .1..0..1..0
..0..0..0..0. .0..0..1..1. .0..0..0..1. .0..1..0..0. .1..0..0..0
CROSSREFS
Cf. A268995.
Sequence in context: A006905 A119400 A182314 * A183606 A366194 A307655
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 17 2016
STATUS
approved