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A327156
a(n) = Product_{d|n, d>1} A008578(1+A286561(n,sigma(d))), where A286561(n,x) gives the highest exponent of x dividing n.
4
1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 8, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 8, 1, 1, 1, 2, 1, 4, 1, 1, 1, 1, 1, 12, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 12, 1, 1, 1, 1, 1, 5, 1, 8, 1, 1, 1, 16, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 12, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 32, 1, 1, 1, 1, 1, 12, 1, 1, 1, 1, 1, 12, 1, 1, 1, 1, 1, 2, 1, 1, 1
OFFSET
1,6
FORMULA
a(n) = Product_{d|n, d>1} A008578(1+A286561(n,sigma(d))), where sigma = A000203.
Other identities. For all n >= 1:
1+A001222(a(n)) = A173441(n).
PROG
(PARI) A327156(n) = { my(m=1, v); fordiv(n, d, if((d>1) && ((v = valuation(n, sigma(d)))>0), m *= prime(v))); (m); };
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 18 2019
STATUS
approved