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%I #10 Jun 09 2024 09:04:16
%S 0,1,16,564,27231,1625324,110854838,8306977585,667683610221
%N Number of chiral immersions of oriented circle into oriented sphere with 2n double points.
%H Robert Coquereaux and Jean-Bernard Zuber, <a href="https://doi.org/10.1142/S0218216516500474">Maps, immersions and permutations</a>, Journal of Knot Theory and Its Ramifications, Vol. 25, No. 8 (2016), 1650047; <a href="https://arxiv.org/abs/1507.03163">arXiv preprint</a>, arXiv:1507.03163 [math.CO], 2015-2016. See Eq. (17), s_m.
%F a(n) = A008986(2*n) - A008988(2*n). - _Andrey Zabolotskiy_, Jun 05 2024
%Y Cf. A008986, A008987, A268565.
%K nonn,more
%O 0,3
%A _N. J. A. Sloane_, Mar 03 2016
%E Name clarified and a(0), a(6)-a(8) added using formula by _Andrey Zabolotskiy_, Jun 08 2024