Double factorial of even numbers: (2n)!! = 2^n*n!.
1, 2, 8, 48, 384, 3840, 46080, 645120, 10321920, 185794560, 3715891200
7 seqfan posts
Sat Jan 7 20:22:49 CET 2012 [seqfan] Re: An unanswered question regarding A058927,A058928
Sat Jan 7 17:10:22 CET 2012 [seqfan] An unanswered question regarding A058927,A058928
Wed Jan 4 06:36:16 CET 2012 [seqfan] Re: A058927
Fri Oct 29 05:35:16 CEST 2010 [seqfan] Implementing first 500 sequences in Java
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
Tue Oct 20 13:41:09 CEST 2009 [seqfan] Re: definition of double factorial
Index of A-numbers in seqfan: by ascending order
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