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 A207518 #7 Jul 22 2025 20:32:16 %S A207518 31,961,6115,68807,600283,5849409,54373655,516879019,4866171581, %T A207518 46008055407,434073335621,4098491207569,38682074952657, %U A207518 365164477339623,3447077980972367,32541367521606267,307192500866436479 %N A207518 Number of nX7 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 1 0 and 1 0 1 vertically. %C A207518 Column 7 of A207519 %H A207518 R. H. Hardin, <a href="/A207518/b207518.txt">Table of n, a(n) for n = 1..210</a> %e A207518 Some solutions for n=4 %e A207518 ..0..0..0..0..0..0..0....1..0..0..0..0..0..0....0..0..0..0..0..0..0 %e A207518 ..0..0..0..0..0..0..0....1..1..1..1..1..0..0....1..0..1..1..0..0..0 %e A207518 ..1..1..1..1..1..0..1....0..1..1..1..1..0..0....1..1..1..1..0..0..0 %e A207518 ..1..1..1..1..1..1..1....0..0..0..0..0..0..0....1..1..0..1..1..0..0 %K A207518 nonn %O A207518 1,1 %A A207518 _R. H. Hardin_ Feb 18 2012