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A373249
a(n) = A181819(n) / gcd(n, A181819(n)), where A181819(n) is the prime shadow of n.
3
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
OFFSET
1,3
LINKS
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
Cf. A325755 (positions of 1's), A353566 (their characteristic function).
Sequence in context: A187757 A286529 A306225 * A077199 A145390 A270026
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 30 2024
STATUS
approved