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%I #7 Jan 17 2025 12:29:28
%S 0,1,4,19,106,709,5356,44558,397146,3716039,35967272,356784008,
%T 3605014966,36955965852,383320824698
%N a(n) = number of non-orientable genus 1 maps with n edges.
%H Evgeniy Krasko and Alexander Omelchenko, <a href="https://arxiv.org/abs/1712.10139">Enumeration of Unsensed Orientable Maps on Surfaces of a Given Genus</a>, arXiv:1712.10139 [math.CO], 2017, see Appendix Table 5.
%Y Column k=1 of A380235.
%Y Cf. A348803, A348804, A348805, A348806, A348807, A348808, A348809, A348810, A348811.
%K nonn,more,changed
%O 0,3
%A _Michael De Vlieger_, Nov 01 2021