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%I #6 Jan 14 2020 09:56:38
%S 1,9,57,847,15303
%N Related to enumeration of branched orientable surface coverings over a non-orientable surface.
%C See reference for more information.
%H I. P. Goulden, J. H. Kwak and J. Lee, <a href="https://doi.org/10.1016/j.disc.2003.10.030">Enumerating branched orientable surface coverings over a non-orientable surface</a>, Discr. Math. 303 (2005), 42-55.
%K nonn,more
%O 1,2
%A _N. J. A. Sloane_, Dec 23 2005