A328475 Convert the primorial base expansion of n into its prime product form, then divide by the largest primorial which divides that product: a(n) = A111701(A276086(n)).

1, 1, 3, 1, 9, 3, 5, 5, 15, 1, 45, 3, 25, 25, 75, 5, 225, 15, 125, 125, 375, 25, 1125, 75, 625, 625, 1875, 125, 5625, 375, 7, 7, 21, 7, 63, 21, 35, 35, 105, 1, 315, 3, 175, 175, 525, 5, 1575, 15, 875, 875, 2625, 25, 7875, 75, 4375, 4375, 13125, 125, 39375, 375, 49, 49, 147, 49, 441, 147, 245, 245, 735, 7, 2205, 21, 1225, 1225, 3675, 35, 11025, 105

Offset: 0

Author

Antti Karttunen, Oct 19 2019

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 0..2559
• Antti Karttunen, Data supplement: n, a(n) computed for n = 0..32768
• Index entries for sequences related to primorial base

Crossrefs

Cf. A002110, A053589, A111701, A276086, A328476, A328399 (rgs-transform).

Cf. A143293 (indices of 1's after a(0)=1).

Programs

PARI

A111701(n) = forprime(p=2, , if(n%p, return(n), n /= p));
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A328475(n) = A111701(A276086(n));

Formula

a(n) = A111701(A276086(n)).