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 A218891 #7 Jul 23 2025 00:07:51 %S A218891 2,6,72,1096,54726,4575512,969423130,418239229652,408299236290280, %T A218891 866521302130938818 %N A218891 Number of n X n arrays of the minimum value of corresponding elements and their horizontal, diagonal or antidiagonal neighbors in a random 0..1 n X n array. %C A218891 Diagonal of A218897 %e A218891 Some solutions for n=3 %e A218891 ..1..0..0....0..0..1....0..0..0....1..0..1....0..0..1....0..0..0....1..0..0 %e A218891 ..1..0..1....1..0..0....0..0..0....0..0..1....1..0..0....0..0..0....1..0..1 %e A218891 ..1..0..0....0..0..0....1..0..0....0..0..1....1..0..0....0..0..0....0..0..1 %K A218891 nonn %O A218891 1,1 %A A218891 _R. H. Hardin_ Nov 08 2012