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%I #5 Mar 30 2012 17:35:17
%S 1,1,1,2,1,3,3,1,3,3,7,5,1,3,4,8,10,14,7,1,3,4,8,3,19,17,6,32,26,11,1,
%T 3,4,8,4,19,18,11,14,63,34,29,75,45,15,1,3,4,8,4,19,18,3,20,14,64,37,
%U 14,39,85,168,62,15,109,167,75,22,1,3,4,8,4,19,18,4,20,14,64,38,11,26,71
%N Number of endofunctions on a set, where the multiset of indegrees forms the n-th partition in Mathematica order (ignoring 0's).
%C Can be regarded as a triangle with one row for each size of partition.
%e For n = 3, the 7 endofunctions are (1,2,3) -> (1,1,1), (1,1,2), (1,2,1), (2,1,1), (1,2,3), (1,3,2) and (2,3,1). In the first, node 1 has indegree 3, the next 3 node 1 has indegree 2 and node 2 has indegree 1 (forming partition [2,1]) and the final 3 are permutations, each node having indegree 1. The partitions of 3 in Mathematica order are [3], [2,1], [1^3], so row 3 of the triangle is 1,3,3.
%e The triangle starts:
%e 1
%e 1
%e 1 2
%e 1 3 3
%e 1 3 3 7 5
%e 1 3 4 8 10 14 7
%K nonn,tabf
%O 0,4
%A _Franklin T. Adams-Watters_, Jan 05 2007
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