[seqfan] Sorting out incorrect versions of sequences

Charles Greathouse charles.greathouse at case.edu
Wed Nov 11 23:38:00 CET 2009

A161563 is described as "Triple factorials n!!!" and begins
1, 1, 2, 6, 40320, 1307674368000, ...

The Math'ca code it gives is n!!!, which is parsed as (n!!)!.  So a(5)
= (5!!)! = 15! = 1307674368000.

Should I mark this as an erroneous version of A007661, or should I
change the definition to "Factorials of double factorials"?  This
seems to have implications for many of the unedited sequences so I
thought I'd ask here.

Charles Greathouse
Case Western Reserve University

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