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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A268749 Number of nX7 binary arrays with some element plus some horizontally or vertically adjacent neighbor totalling two no more than once.

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%I A268749 #4 Feb 12 2016 12:33:35
%S A268749 72,1760,44067,1016807,22577073,487682438,10319681062,215027310572,
%T A268749 4425392044505,90177748184504,1822495416470859,36579128848735042,
%U A268749 729860195814419706,14489046573912834959,286363070886993749567
%N A268749 Number of nX7 binary arrays with some element plus some horizontally or vertically adjacent neighbor totalling two no more than once.
%C A268749 Column 7 of A268750.
%H A268749 R. H. Hardin, <a href="/A268749/b268749.txt">Table of n, a(n) for n = 1..210</a>
%F A268749 Empirical: a(n) = 18*a(n-1) +325*a(n-2) -4074*a(n-3) -48747*a(n-4) +201072*a(n-5) +2225020*a(n-6) -6248320*a(n-7) -47573325*a(n-8) +135873052*a(n-9) +512366407*a(n-10) -1794441336*a(n-11) -2517416282*a(n-12) +13453431136*a(n-13) +1270823811*a(n-14) -55187301646*a(n-15) +38695555999*a(n-16) +115237077158*a(n-17) -158181613013*a(n-18) -96178246900*a(n-19) +263575852534*a(n-20) -18739881048*a(n-21) -224653932202*a(n-22) +90835575680*a(n-23) +105290165907*a(n-24) -69076575582*a(n-25) -27720217521*a(n-26) +26811874806*a(n-27) +3877126783*a(n-28) -6197138172*a(n-29) -207452034*a(n-30) +895782500*a(n-31) -10034133*a(n-32) -81777708*a(n-33) +1520627*a(n-34) +4630616*a(n-35) -28132*a(n-36) -153828*a(n-37) -2195*a(n-38) +2658*a(n-39) +93*a(n-40) -18*a(n-41) -a(n-42)
%e A268749 Some solutions for n=3
%e A268749 ..0..0..1..0..1..0..0. .0..1..1..0..1..0..0. .0..0..0..0..0..1..0
%e A268749 ..1..0..0..1..0..1..0. .0..0..0..0..0..0..1. .0..1..0..1..0..1..0
%e A268749 ..0..0..1..0..0..1..0. .0..0..0..1..0..0..0. .0..0..0..0..0..0..0
%Y A268749 Cf. A268750.
%K A268749 nonn
%O A268749 1,1
%A A268749 _R. H. Hardin_, Feb 12 2016