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 A194613 #8 Jun 03 2025 15:49:15 %S A194613 117,34247,66369488,873084601728,77572756670578163, %T A194613 46519509694797259637061 %N A194613 Half the number of lower triangles of an (n+1) X (n+1) 0..6 array with no element equal to the average of its horizontal and vertical neighbors. %e A194613 Some solutions for 3X3 %e A194613 ..3......6......3......1......3......5......1......4......1......4......6 %e A194613 ..1.2....1.2....4.4....6.0....2.3....2.5....0.5....3.1....5.0....5.4....5.4 %e A194613 ..2.0.6..1.4.5..3.5.2..0.5.1..1.3.0..2.4.1..6.0.2..2.4.5..5.6.4..6.6.4..0.1.2 %Y A194613 Column 6 of A194615. %K A194613 nonn %O A194613 1,1 %A A194613 _R. H. Hardin_, Aug 30 2011