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A339964
a(n) = gcd(sigma(n), n+1).
6
1, 3, 4, 1, 6, 1, 8, 3, 1, 1, 12, 1, 14, 3, 8, 1, 18, 1, 20, 21, 2, 1, 24, 5, 1, 3, 4, 1, 30, 1, 32, 3, 2, 1, 12, 1, 38, 3, 8, 1, 42, 1, 44, 3, 2, 1, 48, 1, 1, 3, 4, 1, 54, 5, 8, 3, 2, 1, 60, 1, 62, 3, 8, 1, 6, 1, 68, 3, 2, 1, 72, 1, 74, 3, 4, 7, 6, 1, 80, 3, 1, 1, 84, 1, 2, 3, 8, 1, 90, 13, 4, 3, 2, 1, 24, 1, 98, 9, 4, 1, 102
OFFSET
1,2
PROG
(PARI) A339964(n) = gcd(sigma(n), n+1);
CROSSREFS
Cf. A339963 (positions of 2's).
Cf. also A049559, A062754.
Sequence in context: A114156 A348972 A354718 * A342915 A276433 A343226
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 25 2020
STATUS
approved