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 A216615 #5 Jul 22 2025 23:33:41 %S A216615 5,203,6097,4213597,942420901,3376465219485,2043835395791757, %T A216615 20538493137072741201 %N A216615 Number of horizontal, diagonal and antidiagonal neighbor colorings of the odd squares of a 7Xn array with new integer colors introduced in row major order. %C A216615 Row 7 of A216612 %e A216615 Some solutions for n=4 %e A216615 ..x..0..x..1....x..0..x..1....x..0..x..1....x..0..x..1....x..0..x..1 %e A216615 ..1..x..2..x....1..x..2..x....1..x..2..x....1..x..2..x....1..x..2..x %e A216615 ..x..0..x..1....x..0..x..3....x..0..x..3....x..0..x..3....x..0..x..3 %e A216615 ..1..x..3..x....2..x..4..x....3..x..4..x....3..x..2..x....4..x..1..x %e A216615 ..x..4..x..5....x..0..x..5....x..5..x..1....x..4..x..5....x..5..x..2 %e A216615 ..0..x..3..x....5..x..6..x....1..x..6..x....3..x..6..x....0..x..4..x %e A216615 ..x..4..x..6....x..7..x..5....x..0..x..4....x..2..x..0....x..1..x..3 %K A216615 nonn %O A216615 1,1 %A A216615 _R. H. Hardin_ Sep 10 2012