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A353668
a(n) = A351546(n) / gcd(n, A351546(n)).
5
1, 1, 4, 7, 6, 2, 8, 5, 13, 1, 12, 7, 14, 4, 8, 31, 18, 13, 20, 1, 32, 2, 24, 1, 31, 7, 8, 2, 30, 4, 32, 7, 16, 1, 48, 91, 38, 10, 56, 1, 42, 16, 44, 7, 26, 4, 48, 31, 57, 31, 24, 49, 54, 4, 72, 5, 16, 5, 60, 2, 62, 16, 104, 127, 12, 8, 68, 7, 32, 8, 72, 13, 74, 19, 124, 35, 96, 28, 80, 31, 121, 7, 84, 8, 108, 22, 8
OFFSET
1,3
PROG
(PARI)
A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A351546(n) = { my(f=factor(sigma(n)), u=A003961(n)); prod(k=1, #f~, f[k, 1]^((0!=(u%f[k, 1]))*f[k, 2])); };
A353668(n) = { my(u=A351546(n)); (u / gcd(n, u)); };
CROSSREFS
Cf. A351552 (positions of 1's).
Sequence in context: A349628 A021025 A078974 * A094641 A200021 A351909
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 04 2022
STATUS
approved