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 A217456 #7 Jul 22 2025 23:40:10 %S A217456 163,16887,2122623,211328743,23851967507,2588934295383, %T A217456 283827195520911,31078249002177539 %N A217456 Number of nX7 arrays of the minimum value of corresponding elements and their horizontal and vertical neighbors in a random 0..2 nX7 array. %C A217456 Column 7 of A217457 %e A217456 Some solutions for n=3 %e A217456 ..0..0..0..2..0..1..0....0..0..0..0..1..0..1....0..0..0..1..2..1..1 %e A217456 ..0..0..2..0..0..0..0....0..0..0..0..0..0..0....0..0..1..2..0..1..0 %e A217456 ..0..1..0..0..0..0..0....0..1..0..0..2..0..1....0..0..1..0..0..0..0 %K A217456 nonn %O A217456 1,1 %A A217456 _R. H. Hardin_ Oct 03 2012