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 A268777 Number of n X 4 binary arrays with some element plus some horizontally, vertically, diagonally or antidiagonally adjacent neighbor totalling two no more than once. 1
 13, 65, 316, 1462, 6383, 27531, 115391, 478849, 1957904, 7940136, 31916445, 127480373, 506131101, 1999695453, 7865869056, 30823236470, 120372357259, 468663337303, 1819741296607, 7048393305965, 27239539562644, 105056982554032 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 4*a(n-1) + 10*a(n-2) - 32*a(n-3) - 47*a(n-4) + 40*a(n-5) + 38*a(n-6) - 12*a(n-7) - 9*a(n-8). Empirical g.f.: x*(13 + 13*x - 74*x^2 - 36*x^3 + 66*x^4 + 26*x^5 - 21*x^6 - 9*x^7) / (1 - 2*x - 7*x^2 + 2*x^3 + 3*x^4)^2. - Colin Barker, Jan 15 2019 EXAMPLE Some solutions for n=4: ..0..0..0..0. .1..0..0..0. .0..1..0..0. .1..0..1..0. .0..0..0..1 ..1..0..1..0. .0..0..0..1. .1..0..0..0. .0..0..0..0. .1..0..0..0 ..0..0..1..0. .1..0..0..0. .0..0..0..0. .0..0..1..0. .1..0..0..0 ..1..0..0..0. .1..0..1..0. .1..0..0..0. .1..0..0..1. .0..0..0..1 CROSSREFS Column 4 of A268781. Sequence in context: A067160 A147067 A147075 * A109727 A041320 A058380 Adjacent sequences:  A268774 A268775 A268776 * A268778 A268779 A268780 KEYWORD nonn AUTHOR R. H. Hardin, Feb 13 2016 STATUS approved

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Last modified October 23 06:48 EDT 2019. Contains 328335 sequences. (Running on oeis4.)