A318834 a(n) = Product_{d|n, d<n} A019565(phi(d)), where phi is the Euler totient function A000010.

1, 2, 2, 4, 2, 12, 2, 12, 6, 20, 2, 108, 2, 60, 30, 60, 2, 540, 2, 300, 90, 84, 2, 2700, 10, 140, 90, 2700, 2, 6300, 2, 420, 126, 44, 150, 121500, 2, 132, 210, 10500, 2, 283500, 2, 5292, 3150, 660, 2, 132300, 30, 5500, 66, 14700, 2, 267300, 210, 472500, 198, 1540, 2, 4630500, 2, 4620, 47250, 4620, 350, 873180, 2, 1452, 990

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..4096

Formula

a(n) = Product_{d|n, d<n} A019565(A000010(d)).

A048675(a(n)) = A051953(n).

Prog

(PARI)
A019565(n) = {my(j, v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ From A019565
A318834(n) = { my(m=1); fordiv(n, d, if(d < n, m *= A019565(eulerphi(d)))); m; };

Crossrefs

Cf. A000010, A019565, A318835 (rgs-transform).

Cf. also A293214, A293231, A300834.

Sequence in context: A317942 A296071 A319342 * A353564 A067228 A356543

Adjacent sequences: A318831 A318832 A318833 * A318835 A318836 A318837

Keyword

nonn

Author

Antti Karttunen, Sep 04 2018

Status

approved