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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.

A125699 Table, T(n,k) is the number of connected categories with n morphisms and k objects.

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%I A125699 #14 Feb 16 2025 08:33:04
%S A125699 1,2,7,1,35,6,228,28,2,2237,159,11,31559,1075,77,3,1668997,9389,497,24
%N A125699 Table, T(n,k) is the number of connected categories with n morphisms and k objects.
%C A125699 Connected in the sense that if the morphism direction and composition is ignored, resulting in a multigraph, that multigraph is connected.
%H A125699 Ben Spitz, <a href="https://github.com/diracdeltafunk/SmallCategories#statistics">SmallCategories</a>
%H A125699 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Category.html">Category</a>
%e A125699 The table starts:
%e A125699         1;
%e A125699         2;
%e A125699         7,    1;
%e A125699        35,    6;
%e A125699       228,   28,   2;
%e A125699      2237,  159,  11;
%e A125699     31559, 1075,  77,  3;
%e A125699   1668997, 9389, 497, 24;
%e A125699   ...
%Y A125699 Cf. A125696, A125698 (row sums), A110654 (row lengths), A058129 (column 1), A125700 (diagonal sums), A125702 (T(2n-1, n)).
%K A125699 tabf,hard,more,nonn
%O A125699 1,2
%A A125699 _Franklin T. Adams-Watters_ and _Christian G. Bower_, Jan 05 2007
%E A125699 a(14)-a(20) from _Ben Spitz_, Sep 02 2023