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 A195802 #6 Jul 22 2025 12:46:50 %S A195802 1,1,6,216,5052,1274808,6711447312 %N A195802 Number of triangular nXnXn 0..5 arrays with all rows and diagonals having the same length having the same sum, with corners zero. %C A195802 Column 5 of A195805 %e A195802 Some solutions for n=5 %e A195802 ......0..........0..........0..........0..........0..........0..........0 %e A195802 .....4.3........4.3........1.2........3.2........5.4........2.1........4.5 %e A195802 ....4.4.3......4.2.3......5.5.2......1.4.0......3.5.4......4.0.5......2.1.1 %e A195802 ...3.2.3.5....3.0.1.5....1.2.5.3....2.2.3.4....5.4.3.5....1.2.1.1....4.2.3.4 %e A195802 ..0.4.5.2.0..0.4.5.2.0..0.2.5.0.0..0.3.2.1.0..0.4.5.4.0..0.2.3.2.0..0.5.0.5.0 %K A195802 nonn %O A195802 1,3 %A A195802 _R. H. Hardin_ Sep 23 2011