A358972 a(n) = ((...((n!^(n-1)!)^(n-2)!)^...)^2!)^1!.

1, 2, 36, 36520347436056576

Offset: 1

Author

Arsen Vardanyan, Dec 07 2022

Keywords

• nonn

Comments

Like n!^(n-1!)^...^2!^1! (A073581), but with all power operators nested from the left.

This sequence grows roughly doubly-exponentially. - Charles R Greathouse IV, Dec 07 2022

Examples

			a(4) = ((4!^3!)^2!)^1! = (24^6)^2 = 191102976^2 = 36520347436056576
		

Links

• Arsen Vardanyan, Table of n, a(n) for n = 1..5

Crossrefs

Cf. A000178, A067039.

Cf. A073581 (exponents right to left).

Programs

PARI

a(n) = n!^prod(i=2,n-1,i^(n-i)); \\ Kevin Ryde, Dec 09 2022

Formula

a(n) = n!^A000178(n-1). - Charles R Greathouse IV, Dec 07 2022

log log a(n) ~ 0.5*n^2*log^2 n. - Charles R Greathouse IV, Dec 07 2022