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 A214543 #6 Dec 31 2023 17:11:40 %S A214543 2,1007,5360,35567,155102,562559,1786114,4984385,12779966,30245569, %T A214543 67041880,140742983,281169008,538998923,995176292,1777352885, %U A214543 3082346868,5202996925,8574228434,13820760479,21832252746,33858093487,51616202234 %N A214543 Number of 5 X 5 X 5 triangular 0..n 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 A214543 Row 5 of A214540. %H A214543 R. H. Hardin, <a href="/A214543/b214543.txt">Table of n, a(n) for n = 1..25</a> %e A214543 Some solutions for n=4 %e A214543 ......2..........2..........2..........2..........2..........2..........3 %e A214543 .....2.2........2.2........3.1........1.3........2.2........1.3........3.3 %e A214543 ....2.2.2......2.2.2......2.3.1......1.2.3......4.2.0......1.3.2......3.3.3 %e A214543 ...2.1.2.3....3.0.2.3....0.3.4.1....1.2.2.3....4.2.0.2....1.3.1.3....4.1.3.4 %e A214543 ..0.3.1.3.3..1.4.0.4.1..1.0.4.1.4..0.2.2.4.2..4.3.1.0.2..1.2.4.0.3..4.4.1.4.2 %Y A214543 Cf. A214540. %K A214543 nonn %O A214543 1,1 %A A214543 _R. H. Hardin_, Jul 20 2012