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A331310
a(n) = gcd(n, A293442(n)).
3
1, 2, 1, 1, 1, 2, 1, 2, 3, 2, 1, 6, 1, 2, 1, 1, 1, 6, 1, 2, 1, 2, 1, 12, 1, 2, 3, 2, 1, 2, 1, 2, 1, 2, 1, 9, 1, 2, 1, 4, 1, 2, 1, 2, 3, 2, 1, 2, 1, 2, 1, 2, 1, 6, 1, 4, 1, 2, 1, 12, 1, 2, 3, 1, 1, 2, 1, 2, 1, 2, 1, 18, 1, 2, 3, 2, 1, 2, 1, 10, 1, 2, 1, 12, 1, 2, 1, 4, 1, 6, 1, 2, 1, 2, 1, 4, 1, 2, 3, 1, 1, 2, 1, 4, 1
OFFSET
1,2
LINKS
FORMULA
a(n) = gcd(n, A293442(n)).
A331310(n) = A331287(n) / A331311(n).
PROG
(PARI)
A019565(n) = {my(j, v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ From A019565
A293442(n) = factorback(apply(e -> A019565(e), factor(n)[, 2]));
A331310(n) = gcd(n, A293442(n));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 20 2020
STATUS
approved