A074319 Product of next n factorials.

2, 144, 2073600, 17557585920000, 192668014586363904000000, 5116462645455544976110780416000000000, 551096864092633744724294766310605805584384000000000000

Offset: 1

Author

Zak Seidov, Sep 22 2002

Keywords

• nonn

Comments

Product of next n factorials gives this sequence, while product of first n factorials = superfactorial is A000178. If superfactorial is sf(n) then this function, "uppersuperfactorial", is usf(n)= sf(2n)/sf(n).

Crossrefs

Cf. A000178.

Programs

Mathematica

Table[Product[i!, {i, n+1, 2n}], {n, 10}]

Formula

product(i!, i=n+1, 2n).

a(n) ~ 2^(2*n^2 + 5*n/2 + 5/12) * n^(n*(3*n/2+1)) * Pi^(n/2) / exp(n*(9*n+4)/4). - Vaclav Kotesovec, Jul 11 2015