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 A324239 #17 Feb 16 2025 08:33:57 %S A324239 1,0,1,0,2,0,4,2,0,11,10,0,34,76,2,0,156,682,15,0,1044,9864,207,2,0, %T A324239 12346,245518,3197,19,0,274668,11366961,74614,326,2 %N A324239 Irregular triangle read by rows: T(n,k) is the number of simple connected graphs on n nodes with radius k, (0 <= k <= floor(n/2)). %H A324239 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/GraphRadius.html">Graph Radius</a> %H A324239 Wikipedia, <a href="https://en.wikipedia.org/wiki/Distance_(graph_theory)">Distance (graph theory)</a> %e A324239 Triangle begins: %e A324239 1; %e A324239 0, 1; %e A324239 0, 2; %e A324239 0, 4, 2; %e A324239 0, 11, 10; %e A324239 0, 34, 76, 2; %e A324239 0, 156, 682, 15; %e A324239 0, 1044, 9864, 207, 2; %e A324239 0, 12346, 245518, 3197, 19; %e A324239 0, 274668, 11366961, 74614, 326, 2; %e A324239 ... %Y A324239 Row sums give A001349. %Y A324239 Columns k=1..2 are A000088(n-1), A324061. %Y A324239 Cf. A283826, A294522, A294525, A324244. %K A324239 nonn,tabf,more %O A324239 1,5 %A A324239 _Andrew Howroyd_, Sep 02 2019