|
%I #5 Dec 07 2020 12:37:30
%S 1,1,4,2,40,80,672,3360,1008,16128,161280,185472
%N Triangle read by rows: T(n,k) = orientable embedding number gamma_k for bouquet B_n, n >= 0, 0 <= k <= [n/2].
%D Jonathan L. Gross and Thomas W. Tucker, Enumerating graph embeddings and partial-duals by genus and Euler genus, ECA 1:1 (2021) Article S2S1. See Table 1. (Beware errors!)
%D J. L. Gross and J. Yellen, eds., Handbook of Graph Theory, CRC Press, 2004; p. 649.
%F Reference gives a recurrence.
%e Triangle begins:
%e 1
%e 1
%e 4 2
%e 40 80
%e 672 3360 1008
%e 16128 161280 185472
%Y Columns give A005431, A123828. Row sums are (2n-1)1.
%K nonn,tabf,more
%O 0,3
%A _N. J. A. Sloane_, Nov 19 2006
|
