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%I #22 Dec 11 2023 11:44:19
%S 1,720,479001600,6402373705728000,620448401733239439360000,
%T 265252859812191058636308480000000,
%U 371993326789901217467999448150835200000000,1405006117752879898543142606244511569936384000000000,12413915592536072670862289047373375038521486354677760000000000
%N a(n) = (6*n)!
%H Vincenzo Librandi, <a href="/A195390/b195390.txt">Table of n, a(n) for n = 0..75</a>
%F From _Amiram Eldar_, Apr 03 2021: (Start)
%F a(n) = A000142(A008588(n)).
%F Sum_{n>=0} 1/a(n) = A332892. (End)
%t (6*Range[0,10])! (* _Harvey P. Dale_, Dec 16 2013 *)
%o (Magma) [Factorial(6*n): n in [0..10]]
%Y Cf. A000142, A008588, A010050, A100732, A100733, A100734, A271946, A332892.
%K nonn,easy
%O 0,2
%A _Vincenzo Librandi_, Sep 24 2011