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 A363685 #17 Sep 22 2023 05:36:13 %S A363685 1,1,0,1,1,0,1,1,1,1,1,0,1,1,0,1,1,2,2,3,2,4,3,4,3,4,2,3,2,2,1,1,0,1, %T A363685 1,0,1,1,2,3,4,4,7,7,10,11,14,14,18,18,21,21,23,22,25,22,23,21,21,18, %U A363685 18,14,14,11,10,7,7,4,4,3,2,1,1,0,1 %N A363685 Irregular triangle read by rows: T(n,k) is the number of descending plane partitions of order n with the sum of the parts equal to k. %F A363685 T(0, 0) = 1, T(1, 0) = 1, T(n, k) = 0 for k < 0 or k > (1/3)*(n+1)*n*(n-1). %e A363685 Rows 1 through 5 are %e A363685 1; %e A363685 1, 0, 1; %e A363685 1, 0, 1, 1, 1, 1, 1, 0, 1; %e A363685 1, 0, 1, 1, 2, 2, 3, 2, 4, 3, 4, 3, 4, 2, 3, 2, 2, 1, 1, 0, 1; %e A363685 1, 0, 1, 1, 2, 3, 4, 4, 7, 7, 10, 11, 14, 14, 18, 18, 21, 21, 23, 22, 25, 22, 23, 21, 21, 18, 18, 14, 14, 11, 10, 7, 7, 4, 4, 3, 2, 1, 1, 0, 1. %Y A363685 Row sums give A005130. %Y A363685 Cf. A198890, A005130, A064999. %K A363685 nonn,tabf %O A363685 1,18 %A A363685 _Ludovic Schwob_, Jun 15 2023