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 A214535 #5 Jul 22 2025 23:16:53 %S A214535 4,8,38,344,5360,141470,6042900,420213820,47817344852,8897304579262 %N A214535 Number of nXnXn triangular 0..3 arrays with no element lying outside the (possibly reversed) range delimited by its sw and se neighbors, and every horizontal row having the same average value. %C A214535 Column 3 of A214540 %e A214535 Some solutions for n=4 %e A214535 .....2........1........1........2........2........1........1........2 %e A214535 ....2.2......1.1......1.1......1.3......2.2......1.1......0.2......2.2 %e A214535 ...1.3.2....1.2.0....1.1.1....2.1.3....1.3.2....2.1.0....1.0.2....1.2.3 %e A214535 ..3.0.3.2..1.2.1.0..2.1.1.0..3.0.2.3..0.3.3.2..0.3.0.1..2.0.0.2..2.0.3.3 %K A214535 nonn %O A214535 1,1 %A A214535 _R. H. Hardin_ Jul 20 2012