Double factorials n!!: a(n)=n*a(n-2), a(0)=a(1)=1.
1, 1, 2, 3, 8, 15, 48, 105, 384, 945, 3840, 10395, 46080, 135135, 645120, 2027025
3 seqfan posts
Sat Oct 24 23:21:26 CEST 2009 [seqfan] Re: more on double factorials/Penson
Wed Oct 21 18:54:36 CEST 2009 [seqfan] Re: more on double factorials/Penson
Tue Oct 20 21:06:35 CEST 2009 [seqfan] more on double factorials/Penson
Index of A-numbers in seqfan: by ascending order
by month
by frequency
by keyword
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