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 A216024 #7 Jan 27 2022 22:20:06 %S A216024 1,2,4,371,146327,10311562327 %N A216024 Number of horizontal, vertical and diagonal neighbor colorings of the odd squares of an n X n array with new integer colors introduced in row major order. %C A216024 Diagonal of A216031. %e A216024 Some solutions for n=4 %e A216024 ..x..0..x..1....x..0..x..1....x..0..x..1....x..0..x..1....x..0..x..1 %e A216024 ..2..x..3..x....0..x..2..x....2..x..3..x....2..x..3..x....2..x..3..x %e A216024 ..x..3..x..4....x..1..x..0....x..3..x..0....x..4..x..2....x..1..x..4 %e A216024 ..3..x..0..x....3..x..0..x....4..x..2..x....5..x..2..x....1..x..0..x %Y A216024 Cf. A216031. %K A216024 nonn %O A216024 1,2 %A A216024 _R. H. Hardin_, Aug 30 2012