A179268 Product of numbers between and including n and n^2.

1, 24, 181440, 3487131648000, 646300418472124416000000, 3099944389915843478899995401256960000000, 844835922269816056767016893501799134566045599137792000000000

Offset: 1

Author

Reinhard Zumkeller, Jul 06 2010

Keywords

• nonn

Comments

a(n) = Product_{k=n..n^2} k;

a(n) = A088020(n)/A000142(n-1).

Examples

			a(2) = 2*3*4 = 24;
a(3) = 3*4*5*6*7*8*9 = 181440.
		

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..23

Crossrefs

Cf. A126804, A027441.

Programs

Magma

[Factorial(n^2) / Factorial(n-1): n in [1..10]]; // Vincenzo Librandi, May 31 2011

Mathematica

Table[Times@@Range[n,n^2],{n,10}] (* Harvey P. Dale, Sep 16 2020 *)

Formula

a(n) = (n^2)! / (n-1)!.

Extensions

Definition clarified by Harvey P. Dale, Sep 16 2020