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 A318062 Number of nX2 0..1 arrays with every element unequal to 1, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
 1, 5, 18, 67, 249, 925, 3437, 12770, 47447, 176289, 655001, 2433653, 9042226, 33596347, 124827065, 463794357, 1723225693, 6402636738, 23788965871, 88387787777, 328404398513, 1220184956261, 4533591310674, 16844536614515 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Column 2 of A318068. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 3*a(n-1) +3*a(n-2) -a(n-3) -a(n-4) EXAMPLE Some solutions for n=5 ..0..1. .0..0. .0..1. .0..0. .0..0. .0..0. .0..0. .0..1. .0..1. .0..1 ..1..1. .1..0. .0..0. .1..1. .1..1. .1..0. .1..0. .1..0. .0..0. .0..1 ..0..1. .0..0. .1..0. .0..1. .1..0. .1..1. .0..1. .0..1. .1..0. .0..0 ..0..0. .0..1. .0..0. .1..1. .1..0. .0..0. .1..1. .0..1. .1..1. .1..1 ..1..1. .0..0. .1..1. .0..1. .1..0. .1..1. .0..1. .1..0. .0..0. .1..0 CROSSREFS Cf. A318068. Sequence in context: A225015 A371871 A166677 * A158879 A322497 A279488 Adjacent sequences: A318059 A318060 A318061 * A318063 A318064 A318065 KEYWORD nonn AUTHOR R. H. Hardin, Aug 15 2018 STATUS approved

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Last modified April 24 06:07 EDT 2024. Contains 371918 sequences. (Running on oeis4.)