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A323071
a(n) = gcd(n, 1+A060681(n)).
5
1, 2, 3, 1, 5, 2, 7, 1, 1, 2, 11, 1, 13, 2, 1, 1, 17, 2, 19, 1, 3, 2, 23, 1, 1, 2, 1, 1, 29, 2, 31, 1, 1, 2, 1, 1, 37, 2, 3, 1, 41, 2, 43, 1, 1, 2, 47, 1, 1, 2, 1, 1, 53, 2, 5, 1, 3, 2, 59, 1, 61, 2, 1, 1, 1, 2, 67, 1, 1, 2, 71, 1, 73, 2, 3, 1, 1, 2, 79, 1, 1, 2, 83, 1, 1, 2, 1, 1, 89, 2, 1, 1, 3, 2, 1, 1, 97, 2, 1, 1, 101, 2, 103, 1, 1
OFFSET
1,2
COMMENTS
Differs from A055023 at n = 55, 105, 155, ..., (A323070).
FORMULA
a(n) = gcd(n, 1+A060681(n)).
a(n) = n/A323072(n).
PROG
(PARI)
A060681(n) = (n-if(1==n, n, n/vecmin(factor(n)[, 1])));
A323071(n) = gcd(n, 1+A060681(n));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 04 2019
STATUS
approved