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%I #4 Dec 05 2013 19:56:46
%S 1,2,144,2073600,17557585920000,192668014586363904000000,
%T 5116462645455544976110780416000000000
%N Product of factorials of next n numbers.
%C Essentially the same as A074319. [From _R. J. Mathar_, Sep 08 2008]
%e a(1)=2!=2, a(2)=3!*4!=144, a(3)=4!*5!*6!, a(4)=5!*6!*7!*8!.
%o (PARI) a(n)=prod(i=n+1,2*n,i!)
%K nonn
%O 1,2
%A _Amarnath Murthy_, Mar 29 2004
%E Corrected and extended by Mohammed Bouayoun (bouyao(AT)wanadoo.fr), Mar 29 2004
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