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

1, 2, 36, 36520347436056576

Offset

1,2

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

Links

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

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

Example

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

Prog

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

Crossrefs

Cf. A000178, A067039.

Cf. A073581 (exponents right to left).

Sequence in context: A283261 A280420 A051459 * A073581 A078081 A077772

Adjacent sequences: A358969 A358970 A358971 * A358973 A358974 A358975

Keyword

nonn

Author

Arsen Vardanyan, Dec 07 2022

Status

approved