A349785 a(n) = 1 + Product_{k=1..n-1} a(gcd(n,k)).

2, 3, 5, 13, 17, 181, 65, 1873, 1601, 22033, 1025, 110120401, 4097, 3032641, 46240001, 6563711233, 65537, 61178101070401, 262145, 3771115818193153, 270400000001, 61977830401, 4194305, 27719934186822773256934560001, 87578116097, 8918277230593, 10498871296000001

Offset

1,1

Links

Table of n, a(n) for n=1..27.

Formula

a(n) = 1 + Product_{d|n, d < n} a(d)^phi(n/d).

Mathematica

a[n_] := a[n] = 1 + Product[a[GCD[n, k]], {k, 1, n - 1}]; Table[a[n], {n, 1, 27}]

Crossrefs

Cf. A000010, A000058, A051190, A338750, A343390.

Sequence in context: A087523 A073919 A162573 * A087356 A281598 A042261

Adjacent sequences: A349782 A349783 A349784 * A349786 A349787 A349788

Keyword

nonn

Author

Ilya Gutkovskiy, Nov 30 2021

Status

approved