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A348969
a(n) = n / gcd(n, A099377(n)).
3
1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 2, 1, 2, 3, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 28, 1, 3, 1, 1, 3, 1, 1, 1, 1, 1, 1, 5, 1, 6, 1, 2, 1, 2, 1, 2, 1, 1, 3, 1, 1, 3, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 6, 1, 1, 3, 2, 1, 1, 1, 1, 1, 2, 1, 3, 1, 1, 1, 1, 1, 28, 1, 1, 3, 1, 1, 3, 7, 4, 1, 2, 5, 3, 1, 1, 1, 1, 1, 3, 1, 1, 3
OFFSET
1,6
FORMULA
a(n) = n / A348968(n) = n / gcd(n, A099377(n)).
PROG
(PARI)
A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A099377(n) = { my(d=divisors(n)); numerator(#d/sum(k=1, #d, 1/d[k])); }; \\ From A099377
A348969(n) = (n / gcd(n, A099377(n)));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 05 2021
STATUS
approved