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 A302209 #4 Apr 03 2018 11:59:48 %S A302209 1,34,32,111,448,1725,6423,24927,96909,373007,1440865,5580691, %T A302209 21589993,83526057,323320869,1251515211,4844117367,18751251811, %U A302209 72587463435,280991282231,1087753936319,4210898294795,16301265698437,63105914070197 %N A302209 Number of nX5 0..1 arrays with every element equal to 0, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. %C A302209 Column 5 of A302212. %H A302209 R. H. Hardin, <a href="/A302209/b302209.txt">Table of n, a(n) for n = 1..210</a> %F A302209 Empirical: a(n) = 7*a(n-1) -16*a(n-2) +43*a(n-3) -167*a(n-4) +289*a(n-5) -491*a(n-6) +1395*a(n-7) -1918*a(n-8) +2105*a(n-9) -4845*a(n-10) +5894*a(n-11) -2484*a(n-12) +7527*a(n-13) -10198*a(n-14) -8382*a(n-15) -6549*a(n-16) +12610*a(n-17) +32961*a(n-18) +12280*a(n-19) -7213*a(n-20) -49277*a(n-21) -21675*a(n-22) -15454*a(n-23) +41277*a(n-24) +12068*a(n-25) +27412*a(n-26) -15746*a(n-27) +1598*a(n-28) -14336*a(n-29) +2718*a(n-30) -5912*a(n-31) +3644*a(n-32) -1164*a(n-33) +2304*a(n-34) -272*a(n-35) +160*a(n-36) -192*a(n-37) for n>41 %e A302209 Some solutions for n=5 %e A302209 ..0..1..1..0..0. .0..1..1..0..0. .0..0..1..1..0. .0..1..1..0..0 %e A302209 ..0..1..1..0..0. .1..1..0..0..1. .0..0..1..1..0. .1..1..0..0..1 %e A302209 ..0..1..1..0..1. .0..1..1..0..1. .1..0..1..1..0. .0..1..1..0..1 %e A302209 ..1..1..0..0..1. .0..1..1..0..0. .1..0..0..1..1. .1..1..0..0..0 %e A302209 ..1..1..0..0..0. .1..1..0..0..0. .0..0..0..1..1. .1..1..0..0..1 %Y A302209 Cf. A302212. %K A302209 nonn %O A302209 1,2 %A A302209 _R. H. Hardin_, Apr 03 2018