A349000 a(n) = A323166(A276086(n)), where A323166(n) = gcd(n, usigma(n)), usigma (A034448) is multiplicative with a(p^e) = (p^e)+1, and A276086 gives the prime product form of primorial base expansion of n.

1, 1, 1, 6, 1, 6, 1, 2, 3, 6, 15, 90, 1, 2, 1, 6, 5, 30, 1, 2, 3, 6, 45, 90, 1, 2, 1, 6, 5, 30, 1, 2, 1, 6, 1, 6, 1, 2, 3, 6, 15, 90, 1, 2, 1, 6, 5, 30, 7, 14, 21, 42, 315, 630, 1, 2, 1, 6, 5, 30, 1, 2, 1, 6, 1, 6, 5, 10, 15, 30, 15, 90, 25, 50, 25, 150, 25, 150, 175, 350, 525, 1050, 7875, 15750, 25, 50, 25, 150, 125, 750

Offset

0,4

Links

Antti Karttunen, Table of n, a(n) for n = 0..11550

Index entries for sequences related to primorial base

Formula

a(n) = A323166(A276086(n)) = gcd(A276086(n), A348996(n)).

Prog

(PARI) A349000(n) = { my(m1=1, m2=1, p=2, u); while(n, if(n%p, u = p^(n%p); m1 *= u; m2 *= (1+u)); n = n\p; p = nextprime(1+p)); gcd(m1, m2); };

Crossrefs

Cf. A034448, A276086, A323166, A348996, A348997, A348999.

Sequence in context: A023406 A138116 A348999 * A344699 A010687 A176355

Adjacent sequences: A348997 A348998 A348999 * A349001 A349002 A349003

Keyword

nonn,base,look

Author

Antti Karttunen, Nov 07 2021

Status

approved