Pseudo-factorials: a(0)=1, a(n+1)=(-1)^(n+1)*sum('binomial(n,k)*a(k)*a(n-k)','k'=0..n), n>=0.
1, 1, 2, 2, 16, 40, 320, 1040, 12160, 52480, 742400, 3872000, 66457600
4 seqfan posts
Sun Feb 1 22:11:37 CET 2009 [seqfan] Conventions on timestamps?
Sun Feb 1 19:37:28 CET 2009 [seqfan] Re: Conventions on timestamps?
Sun Feb 1 19:28:58 CET 2009 [seqfan] Re: Conventions on timestamps?
Sun Feb 1 18:05:55 CET 2009 [seqfan] Conventions on timestamps?
Index of A-numbers in seqfan: by ascending order
by month
by frequency
by keyword
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