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A269041
Number of 7Xn 0..2 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two exactly once.
1
0, 25272, 357756, 8277072, 159397596, 3266423688, 63310818360, 1232016734502, 23480085224460, 445037745455958, 8347562556153996, 155656709783860410, 2883687582601214532, 53163977044543395168, 975616567564729165860
OFFSET
1,2
COMMENTS
Row 7 of A269035.
FORMULA
Empirical recurrence of order 92 (see link above)
EXAMPLE
Some solutions for n=2
..0..0. .1..2. .2..2. .0..0. .1..2. .1..0. .1..0. .1..2. .1..0. .2..2
..1..1. .1..2. .2..1. .1..0. .2..2. .0..2. .1..0. .1..0. .1..0. .2..1
..2..2. .1..0. .0..1. .1..2. .2..1. .1..0. .0..0. .1..2. .2..2. .0..1
..2..1. .0..1. .0..0. .2..0. .0..2. .1..2. .1..2. .2..2. .2..2. .2..1
..2..2. .0..1. .0..0. .1..2. .2..1. .1..0. .1..0. .1..0. .2..1. .1..2
..2..1. .0..1. .1..0. .2..2. .2..2. .1..2. .0..0. .1..2. .2..2. .1..0
..2..1. .0..1. .2..2. .2..1. .2..2. .1..0. .0..1. .2..2. .2..2. .0..0
CROSSREFS
Cf. A269035.
Sequence in context: A046709 A179723 A174825 * A130615 A175741 A203090
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 18 2016
STATUS
approved