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A344756
a(n) = A003415(n) / gcd(A003415(n), A069359(n)).
4
1, 1, 2, 1, 1, 1, 3, 2, 1, 1, 8, 1, 1, 1, 4, 1, 7, 1, 12, 1, 1, 1, 11, 2, 1, 3, 16, 1, 1, 1, 5, 1, 1, 1, 2, 1, 1, 1, 17, 1, 1, 1, 24, 13, 1, 1, 14, 2, 9, 1, 28, 1, 9, 1, 23, 1, 1, 1, 46, 1, 1, 17, 6, 1, 1, 1, 36, 1, 1, 1, 13, 1, 1, 11, 40, 1, 1, 1, 22, 4, 1, 1, 62, 1, 1, 1, 35, 1, 41, 1, 48, 1, 1, 1, 17, 1, 11, 25
OFFSET
2,3
FORMULA
a(n) = A003415(n) / A340070(n) = A003415(n) / gcd(A003415(n), A069359(n)).
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A069359(n) = (n*sumdiv(n, d, isprime(d)/d)); \\ From A069359
A344756(n) = { my(u=A003415(n)); (u/gcd(u, A069359(n))); };
CROSSREFS
Cf. A003415, A005117 (for n > 1 gives the positions of ones), A069359, A340070, A344757.
Cf. also A344696.
Sequence in context: A337619 A183214 A346009 * A101221 A086291 A262766
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 28 2021
STATUS
approved