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%I #6 May 03 2023 10:51:49
%S 1,1,3,7,74,1532,478902,1561933881,74069769621942,
%T 44786847731274624558,454923769422460614413179958,
%U 75365529411732671264995255795387368,250450659464630320300793563353757730632329596,16712244262184960007363857016489055045260380508520606142
%N Number of nonisomorphic multisets of involutions on an n-set with n involutions.
%C Isomorphism is up to permutation of the elements of the n-set.
%H Andrew Howroyd, <a href="/A362651/b362651.txt">Table of n, a(n) for n = 0..40</a>
%Y Main diagonal of A362648.
%Y Cf. A362382, A362647.
%K nonn
%O 0,3
%A _Andrew Howroyd_, May 01 2023