A318836 Product_{d|n, dA007431(d) > 0} prime(A007431(d)), where A007431 is the Möbius transform of Euler's totient function.

1, 2, 2, 2, 2, 4, 2, 4, 4, 10, 2, 8, 2, 22, 20, 12, 2, 28, 2, 20, 44, 46, 2, 48, 10, 62, 28, 44, 2, 100, 2, 84, 92, 94, 110, 112, 2, 118, 124, 300, 2, 484, 2, 92, 700, 146, 2, 1008, 22, 530, 188, 124, 2, 1036, 230, 1452, 236, 206, 2, 2000, 2, 218, 3388, 1596, 310, 2116, 2, 188, 292, 5170, 2, 7056, 2, 298, 5300, 236, 506

Offset: 1

Author

Antti Karttunen, Sep 05 2018

Keywords

• nonn

Links

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

Crossrefs

Cf. A007431, A062790, A318837 (rgs-transform).

Cf. also A318838.

Programs

PARI

A007431(n) = sumdiv(n,d,moebius(n/d)*eulerphi(d));
A318836(n) = { my(m=1); fordiv(n,d,if((dA007431(d)!=0),m *= prime(A007431(d)))); (m); };

Formula

a(n) = product_{d|n, dA008578(1+A007431(d)).

For all n >= 1, A056239(a(n)) = A062790(n).