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A329037
a(n) = Product_{d|n, d>1} A008578(1+A286561(A276086(n),d)), where A286561(x,d) gives the exponent of the highest power of d dividing x.
3
1, 1, 2, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 12, 1, 1, 1, 1, 5, 2, 1, 1, 1, 21, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 2, 2, 1, 2, 1, 1, 12, 1, 1, 1, 2, 10, 2, 1, 1, 1, 7, 2, 2, 1, 1, 1, 1, 1, 12, 1, 1, 1, 1, 1, 2, 12, 1, 1, 1, 1, 48, 1, 3, 1, 1, 5, 2, 1, 1, 3, 7, 1, 2, 1, 1, 1, 5, 1, 2, 1, 1, 1, 1, 10, 2, 2, 1, 1, 1, 1, 720
OFFSET
1,3
FORMULA
a(n) = Product_{d|n, d>1} A008578(1+A286561(A276086(n),d)).
1+A001222(a(n)) = A327168(n).
PROG
(PARI)
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A329037(n) = { my(m=1, x=A276086(n), v); fordiv(n, d, if((d>1) && ((v = valuation(x, d))>0), m *= prime(v))); (m); };
CROSSREFS
Cf. also A327167.
Sequence in context: A324119 A083382 A327168 * A279794 A025900 A118383
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 08 2019
STATUS
approved