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%I #15 Sep 08 2022 08:45:15
%S 1,120,3628800,1307674368000,2432902008176640000,
%T 15511210043330985984000000,265252859812191058636308480000000,
%U 10333147966386144929666651337523200000000
%N a(n) = (5*n)!.
%H Vincenzo Librandi, <a href="/A100734/b100734.txt">Table of n, a(n) for n = 0..90</a>
%F E.g.f.: 1/(1-x^5).
%F From _Ilya Gutkovskiy_, Jan 20 2017: (Start)
%F a(n) ~ sqrt(2*Pi)*5^(5*n + 1/2)*n^(5*n + 1/2)/exp(5*n).
%F Sum_{n>=0} 1/a(n) = A269296. (End)
%t (5*Range[0,10])! (* _Harvey P. Dale_, May 06 2015 *)
%o (Magma) [Factorial(5*n): n in [0..10]]; // _Vincenzo Librandi_, Sep 24 2011
%Y Cf. A000142, A010050, A100732, A100733, A268506, A269296.
%K nonn,easy
%O 0,2
%A _Ralf Stephan_, Dec 08 2004
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