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 A268889 Number of 4Xn binary arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once. 1
 0, 71, 462, 4133, 27130, 186732, 1187838, 7529253, 46440962, 283673207, 1710265892, 10226321520, 60660804228, 357586190291, 2096177689750, 12229766790505, 71054027831574, 411303965509420, 2373090804832634 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row 4 of A268886. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 2*a(n-1) +39*a(n-2) +14*a(n-3) -482*a(n-4) -1102*a(n-5) -111*a(n-6) +1758*a(n-7) +982*a(n-8) -1114*a(n-9) -743*a(n-10) +394*a(n-11) +206*a(n-12) -90*a(n-13) -17*a(n-14) +10*a(n-15) -a(n-16) EXAMPLE Some solutions for n=4 ..0..0..0..0. .1..0..1..0. .1..0..0..1. .1..0..0..0. .0..1..0..1 ..0..0..1..0. .0..0..0..0. .1..0..1..0. .1..0..1..0. .1..0..0..1 ..0..0..1..0. .1..0..1..0. .1..0..0..1. .0..1..0..0. .0..1..0..0 ..0..1..0..1. .0..1..0..1. .0..1..0..0. .0..0..0..0. .0..0..0..0 CROSSREFS Cf. A268886. Sequence in context: A201313 A078949 A057541 * A142432 A341426 A250982 Adjacent sequences:  A268886 A268887 A268888 * A268890 A268891 A268892 KEYWORD nonn AUTHOR R. H. Hardin, Feb 15 2016 STATUS approved

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Last modified August 3 15:54 EDT 2021. Contains 346439 sequences. (Running on oeis4.)