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%I #27 Mar 30 2023 06:16:11
%S 1,5,60,1260,40320,1814400,108864000,8382528000,804722688000,
%T 94152554496000,13181357629440000,2174924008857600000,
%U 417585409700659200000,92286375543845683200000,23256166637049112166400000,6628007491558996967424000000
%N a(n) = n!*(n+4)! / 4!.
%H Delbert L. Johnson, <a href="/A010793/b010793.txt">Table of n, a(n) for n = 0..251</a>
%H <a href="/index/Fa#factorial">Index entries for sequences related to factorial numbers</a>.
%F From _Amiram Eldar_, Sep 27 2022: (Start)
%F Sum_{n>=0} 1/a(n) = 24*BesselI(4,2).
%F Sum_{n>=0} (-1)^n/a(n) = 24*BesselJ(4,2). (End)
%p f := n->n!*(n+4)!/4!;
%t Table[n! * (n + 4)!/24, {n, 0, 20}] (* _Amiram Eldar_, Sep 27 2022 *)
%o (PARI) a(n) = n!*(n+4)! / 4!; \\ _Michel Marcus_, Mar 30 2023
%Y Cf. A010791, A010792, A010794, A010795.
%K nonn
%O 0,2
%A _N. J. A. Sloane_
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