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A323160
a(n) = gcd(n, A323159(n)) = gcd(n, A034448(n), A048250(n)).
3
1, 1, 1, 1, 1, 6, 1, 1, 1, 2, 1, 4, 1, 2, 3, 1, 1, 6, 1, 2, 1, 2, 1, 12, 1, 2, 1, 4, 1, 6, 1, 1, 3, 2, 1, 2, 1, 2, 1, 2, 1, 6, 1, 4, 3, 2, 1, 4, 1, 2, 3, 2, 1, 6, 1, 8, 1, 2, 1, 12, 1, 2, 1, 1, 1, 6, 1, 2, 3, 2, 1, 6, 1, 2, 1, 4, 1, 6, 1, 2, 1, 2, 1, 4, 1, 2, 3, 4, 1, 18, 7, 4, 1, 2, 5, 12, 1, 2, 3, 2, 1, 6, 1, 2, 3
OFFSET
1,6
LINKS
FORMULA
a(n) = gcd(n, A323159(n)) = gcd(A048250(n), A323166(n)).
a(n) = gcd(n, A034448(n), A048250(n)).
PROG
(PARI)
A034448(n) = { my(f=factorint(n)); prod(k=1, #f~, 1+(f[k, 1]^f[k, 2])); }; \\ After code in A034448
A048250(n) = factorback(apply(p -> p+1, factor(n)[, 1]));
A323160(n) = gcd(n, gcd(A034448(n), A048250(n)));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 09 2019
STATUS
approved