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 A218424 #6 Jul 22 2025 23:56:58 %S A218424 31,2849,158429,9539915,572765605,34328798853,2058493362799, %T A218424 123428176573409,7400808508179025,443756537313437079, %U A218424 26607874601757021869,1595422183998461122637,95662355032495391763215 %N A218424 Hilltop maps: number of nX6 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal, vertical or antidiagonal neighbor in a random 0..1 nX6 array. %C A218424 Column 6 of A218426 %H A218424 R. H. Hardin, <a href="/A218424/b218424.txt">Table of n, a(n) for n = 1..44</a> %e A218424 Some solutions for n=3 %e A218424 ..1..1..1..1..1..0....1..1..1..0..0..0....0..1..0..0..1..0....1..1..0..0..1..0 %e A218424 ..0..1..1..0..1..1....0..1..1..1..1..0....0..0..1..0..1..0....0..1..0..1..0..1 %e A218424 ..0..1..1..0..1..0....1..1..0..1..0..1....0..1..0..0..1..0....0..1..0..0..1..1 %K A218424 nonn %O A218424 1,1 %A A218424 _R. H. Hardin_ Oct 28 2012