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 A269015 Number of 5Xn binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two exactly once. 1

%I

%S 0,145,1066,14240,109058,1049588,8134304,69184207,534525058,

%T 4286305792,32838001316,255036784680,1935580387968,14746081110093,

%U 110945210978202,834598743197152,6232287294972630,46465158121063708,344786403529703264

%N Number of 5Xn binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two exactly once.

%C Row 5 of A269011.

%H R. H. Hardin, <a href="/A269015/b269015.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 8*a(n-1) +52*a(n-2) -424*a(n-3) -816*a(n-4) +6756*a(n-5) +1362*a(n-6) -38476*a(n-7) +19016*a(n-8) +82920*a(n-9) -70008*a(n-10) -50556*a(n-11) +50607*a(n-12) +9180*a(n-13) -10404*a(n-14)

%e Some solutions for n=4

%e ..0..0..0..0. .0..0..0..1. .1..0..0..1. .1..0..0..0. .1..0..1..0

%e ..0..1..0..0. .0..0..0..1. .1..0..0..1. .0..1..0..0. .1..0..1..0

%e ..0..0..0..0. .0..1..0..0. .0..1..0..0. .0..0..0..1. .1..0..0..1

%e ..1..1..0..1. .1..0..0..0. .0..1..0..0. .0..0..0..0. .0..0..0..0

%e ..0..0..0..1. .0..0..0..0. .0..0..0..1. .0..0..0..1. .0..0..0..1

%Y Cf. A269011.

%K nonn

%O 1,2

%A _R. H. Hardin_, Feb 17 2016

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Last modified December 7 07:53 EST 2021. Contains 349571 sequences. (Running on oeis4.)