A373249 - OEIS

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A373249

a(n) = A181819(n) / gcd(n, A181819(n)), where A181819(n) is the prime shadow of n.

1, 1, 2, 3, 2, 2, 2, 5, 1, 2, 2, 1, 2, 2, 4, 7, 2, 1, 2, 3, 4, 2, 2, 5, 3, 2, 5, 3, 2, 4, 2, 11, 4, 2, 4, 1, 2, 2, 4, 1, 2, 4, 2, 3, 2, 2, 2, 7, 3, 3, 4, 3, 2, 5, 4, 5, 4, 2, 2, 1, 2, 2, 2, 13, 4, 4, 2, 3, 4, 4, 2, 5, 2, 2, 2, 3, 4, 4, 2, 7, 7, 2, 2, 1, 4, 2, 4, 5, 2, 2, 4, 3, 4, 2, 4, 11, 2, 3, 2, 9, 2, 4, 2, 5, 8

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,3

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

FORMULA

a(n) = A181819(n) / A373246(n) = A181819(n) / gcd(n, A181819(n)).

PROG

(PARI)

A181819(n) = factorback(apply(e->prime(e), (factor(n)[, 2])));

A373249(n) = { my(s=A181819(n)); s/gcd(n, s); };

CROSSREFS