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 A218840 #6 Jul 23 2025 00:06:47 %S A218840 21,438,9516,201960,4299802,91513161,1948262831,41475009100, %T A218840 882920599454,18795714385533,400125250527550,8517908622924528, %U A218840 181330147341356981,3860175542316616321,82175828913427711206,1749367816354069818496 %N A218840 Unmatched value maps: number of nX6 binary arrays indicating the locations of corresponding elements not equal to any horizontal or antidiagonal neighbor in a random 0..1 nX6 array. %C A218840 Column 6 of A218842 %H A218840 R. H. Hardin, <a href="/A218840/b218840.txt">Table of n, a(n) for n = 1..26</a> %e A218840 Some solutions for n=3 %e A218840 ..0..0..1..1..1..0....0..0..0..0..1..1....1..0..0..0..0..0....1..0..1..0..0..0 %e A218840 ..1..1..1..0..0..0....0..0..0..0..1..1....1..0..0..0..0..1....0..0..0..1..0..1 %e A218840 ..1..1..1..0..0..1....0..0..0..0..0..0....0..1..1..0..0..1....0..0..0..0..0..1 %K A218840 nonn %O A218840 1,1 %A A218840 _R. H. Hardin_ Nov 07 2012