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.
%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