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%I #8 Sep 16 2025 08:36:24
%S 1,3,41,965,32179,1387617,73376435,4595401239,332576767523,
%T 27309220303937,2508532874244891,254868083994804007,
%U 28378575132862651917,3436475259153967695095,449643047382070812141885,63218449394701421070509745,9505029949439482326271983795
%N Number of partial permutations of [2n] that have exactly n cycles.
%H Alois P. Heinz, <a href="/A388149/b388149.txt">Table of n, a(n) for n = 0..326</a>
%F a(n) = (2n)! * [x^(2n) y^n] exp(x/(1-x))/(1-x)^y.
%F a(n) = A216294(2n,n).
%Y Cf. A216294.
%K nonn
%O 0,2
%A _Alois P. Heinz_, Sep 15 2025