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%I #30 Dec 09 2022 06:17:14
%S 1,2,36,36520347436056576
%N a(n) = ((...((n!^(n-1)!)^(n-2)!)^...)^2!)^1!.
%C Like n!^(n-1!)^...^2!^1! (A073581), but with all power operators nested from the left.
%C This sequence grows roughly doubly-exponentially. - _Charles R Greathouse IV_, Dec 07 2022
%H Arsen Vardanyan, <a href="/A358972/b358972.txt">Table of n, a(n) for n = 1..5</a>
%F a(n) = n!^A000178(n-1). - _Charles R Greathouse IV_, Dec 07 2022
%F log log a(n) ~ 0.5*n^2*log^2 n. - _Charles R Greathouse IV_, Dec 07 2022
%e a(4) = ((4!^3!)^2!)^1! = (24^6)^2 = 191102976^2 = 36520347436056576
%o (PARI) a(n) = n!^prod(i=2,n-1,i^(n-i)); \\ _Kevin Ryde_, Dec 09 2022
%Y Cf. A000178, A067039.
%Y Cf. A073581 (exponents right to left).
%K nonn
%O 1,2
%A _Arsen Vardanyan_, Dec 07 2022