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A268808
Number of nX7 0..2 arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two not more than once.
1
768, 4914, 48460, 640926, 8734264, 115671422, 1508087180, 19390335102, 246666802206, 3110082281974, 38924665296474, 484120668061458, 5988867204857378, 73740656947715536, 904257358969806890
OFFSET
1,1
COMMENTS
Column 7 of A268809.
FORMULA
Empirical recurrence of order 68 (see link above)
EXAMPLE
Some solutions for n=3
..2..2..2..2..2..1..2. .0..0..0..1..0..0..0. .0..0..1..0..1..0..0
..2..2..2..2..2..2..1. .0..0..0..0..1..0..1. .1..0..0..1..0..0..1
..1..2..1..2..1..0..0. .0..1..0..0..0..0..1. .0..1..0..0..1..0..0
CROSSREFS
Cf. A268809.
Sequence in context: A179668 A219317 A281238 * A183687 A269051 A282287
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 13 2016
STATUS
approved