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 A206388 #6 Jul 22 2025 19:26:25 %S A206388 52,62004,21916090,8094257014,2965468376203 %N A206388 Number of nX7 0..6 arrays with no element equal to another within a city block distance of two, and new values 0..6 introduced in row major order. %C A206388 Column 7 of A206389 %e A206388 Some solutions for n=4 %e A206388 ..0..1..2..0..1..2..3....0..1..2..3..0..2..1....0..1..2..0..1..2..0 %e A206388 ..4..3..5..6..3..4..5....4..3..5..4..6..5..0....3..4..5..3..6..4..1 %e A206388 ..1..6..4..1..0..6..1....1..2..6..0..1..3..6....1..2..6..4..2..3..5 %e A206388 ..2..0..3..5..2..3..4....3..4..1..5..2..0..4....4..3..0..5..1..6..4 %K A206388 nonn %O A206388 1,1 %A A206388 _R. H. Hardin_ Feb 07 2012