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 A216790 #6 Jul 22 2025 23:35:24 %S A216790 1,11,5318,22831676,915294166360,348567447145791344 %N A216790 Number of 4-colorings of a side-n hexagonal array with colors introduced in row major order. %C A216790 Column 3 of A216792 %e A216790 Some solutions for n=3 %e A216790 ......0.1.2..........0.1.2..........0.1.2..........0.1.2..........0.1.2 %e A216790 .....1.3.0.1........1.2.0.3........3.2.3.0........3.2.0.1........3.2.3.0 %e A216790 ....3.2.1.2.0......0.3.1.2.1......2.0.1.2.1......2.0.3.2.3......2.1.0.2.1 %e A216790 .....0.3.0.3........1.0.3.0........3.2.0.3........1.2.0.1........0.2.1.3 %e A216790 ......2.1.2..........3.1.2..........0.3.2..........0.1.3..........1.3.0 %K A216790 nonn %O A216790 1,2 %A A216790 _R. H. Hardin_ Sep 16 2012