A304104 a(n) = Product_{d|n, d>1} prime(A304101(d)-1).

1, 2, 2, 6, 2, 20, 3, 12, 10, 20, 3, 420, 2, 30, 20, 60, 11, 300, 11, 420, 12, 30, 5, 4200, 22, 20, 130, 990, 3, 11000, 11, 420, 102, 44, 30, 31500, 5, 242, 20, 10920, 11, 3000, 13, 1170, 1100, 190, 3, 231000, 33, 2420, 506, 420, 19, 66300, 12, 9900, 110, 30, 11, 8085000, 13, 242, 300, 5460, 52, 56100, 19, 660, 130, 19500, 13, 9135000, 11, 290, 4180, 2178, 99

Offset

1,2

Links

Antti Karttunen, Table of n, a(n) for n = 1..4181

Formula

a(n) = Product_{d|n, d>1} A000040(A304101(d)-1).

a(n) = (1/2) * A304102(n) * A000040(A304101(n)-1).

Other identities. For all n >= 1:

A001222(a(n)) = A032741(n).

A001511(a(n)) = A005086(n).

A007949(a(n)) = A304096(n).

Prog

(PARI)
\\ Needs also code from A304101:
A304104(n) = { my(m=1); fordiv(n, d, if(d>1, m *= prime(A304101(d)-1))); (m); };

Crossrefs

Cf. A304101, A304102, A304105 (restricted growth sequence transform of this sequence).

Sequence in context: A098792 A061057 A038667 * A199823 A013608 A369867

Adjacent sequences: A304101 A304102 A304103 * A304105 A304106 A304107

Keyword

nonn

Author

Antti Karttunen, May 13 2018

Status

approved