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a(n) = n! * (n+1)! * (n+2)! / (2! * 3!).
2

%I #21 Aug 14 2023 08:27:45

%S 1,24,1440,172800,36288000,12192768000,6145155072000,4424511651840000,

%T 4380266535321600000,5781951826624512000000,9921829334487662592000000,

%U 21669275266521055100928000000

%N a(n) = n! * (n+1)! * (n+2)! / (2! * 3!).

%H Seiichi Manyama, <a href="/A010797/b010797.txt">Table of n, a(n) for n = 1..180</a>

%H <a href="/index/Fa#factorial">Index entries for sequences related to factorial numbers</a>

%t Times@@@Partition[Range[15]!,3,1]/(2!3!) (* _Harvey P. Dale_, Aug 06 2022 *)

%Y Column 3 in triangle A009963.

%K nonn,easy

%O 1,2

%A _N. J. A. Sloane_

%E Offset changed to 1 by _Seiichi Manyama_, Aug 14 2023