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%I #9 Jun 19 2013 13:54:28
%S 1,0,16,0,7739670528,0,137105941502361600000000000000,0,
%T 6990502336758588607110928994980286070521856000000000000000000,0
%N A lower bound on the number of the distinct maximum genus embedding of the complete bipartite graph K(n,n).
%C Theorem A, p. 3, of Dong.
%H Guanghua Dong, Han Ren, Ning Wang, Yuanqiu Huang, <a href="http://arxiv.org/abs/1203.0855">Lower bound on the number of the maximum genus embedding of K_{n,n}</a>, arXiv:1203.0855 [math.CO]
%F For n odd, a(n) = 2^((n-1)/2)*(n-2)!!^n*(n-1)!^n; otherwise a(n) = 0.
%o (PARI) a(n)=if(n%2,2^(n\2)*prod(i=1,n\2,2*i-1)^n*(n-1)!^n,0) \\ _Charles R Greathouse IV_, Jun 19 2013
%Y Cf. A000142 (factorial numbers), A001147 (double factorial numbers).
%K nonn,easy
%O 1,3
%A _Jonathan Vos Post_, Mar 06 2012
%E Terms corrected by _Charles R Greathouse IV_, Jun 19 2013