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 A296540 #4 Dec 15 2017 08:48:52 %S A296540 1,45,654,5601,53995,560942,5705431,57470370,581613058,5896361722, %T A296540 59744304510,605287549399,6133281385115,62150472842382, %U A296540 629792949015747,6381981797680641,64672057071608258,655359047486913615 %N A296540 Number of nX7 0..1 arrays with each 1 horizontally, vertically or antidiagonally adjacent to 2 or 4 neighboring 1s. %C A296540 Column 7 of A296541. %H A296540 R. H. Hardin, <a href="/A296540/b296540.txt">Table of n, a(n) for n = 1..210</a> %e A296540 Some solutions for n=5 %e A296540 ..0..1..0..1..1..0..0. .0..0..0..1..1..0..0. .0..0..1..0..0..0..0 %e A296540 ..1..1..0..1..0..0..0. .0..1..1..0..1..0..0. .1..1..1..0..0..1..1 %e A296540 ..0..0..0..0..0..0..0. .1..0..0..0..1..0..0. .1..0..0..0..0..1..0 %e A296540 ..0..1..1..0..1..0..0. .1..0..1..1..0..0..0. .0..0..1..0..0..0..0 %e A296540 ..0..1..0..1..1..0..0. .1..1..0..0..0..0..0. .0..1..1..0..0..0..0 %Y A296540 Cf. A296541. %K A296540 nonn %O A296540 1,2 %A A296540 _R. H. Hardin_, Dec 15 2017