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%I #3 Mar 30 2012 18:53:07
%S 1,5,44,1266,72636,6652810,889574412,163459302788,39520825344016,
%T 12164510040883218,4644631106520877974,2154334728240414720022,
%U 1193170003333152768100020,777776389315596583864343748
%N Number of non-equivalent (2n+1)-fold branched coverings of the Klein bottle with one cyclic branch point.
%C No such covering of even multiplicity exists.
%D J. H. Kwak, A. Mednykh and V. Liskovets, Enumeration of branched coverings of nonorientable surfaces with cyclic branch points, SIAM J. Discrete Math., Vol. 19, No. 2 (2005), 388-398.
%F a(n)=2*sum_{k|(2n+1)}k!*((2n+1)/k)^(k-1)*phi((2n+1)/k)/(k+1) where phi(n) is the Euler function A000010.
%Y Cf. A113947, A113950.
%K nonn
%O 0,2
%A _Valery A. Liskovets_, Nov 10 2005
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