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A293515
a(n) = Product_{d^k|n, d>1, k>1} prime(A286561(n,d)-1), where A286561(n,d) gives the highest exponent of d dividing n.
5
1, 1, 1, 2, 1, 1, 1, 3, 2, 1, 1, 2, 1, 1, 1, 10, 1, 2, 1, 2, 1, 1, 1, 3, 2, 1, 3, 2, 1, 1, 1, 14, 1, 1, 1, 8, 1, 1, 1, 3, 1, 1, 1, 2, 2, 1, 1, 10, 2, 2, 1, 2, 1, 3, 1, 3, 1, 1, 1, 2, 1, 1, 2, 66, 1, 1, 1, 2, 1, 1, 1, 12, 1, 1, 2, 2, 1, 1, 1, 10, 10, 1, 1, 2, 1, 1, 1, 3, 1, 2, 1, 2, 1, 1, 1, 14, 1, 2, 2, 8, 1, 1, 1, 3, 1, 1, 1, 12, 1, 1, 1, 10, 1, 1, 1, 2, 2
OFFSET
1,4
FORMULA
a(n) = Product_{d|n, d>1} A008578(A286561(n,d)).
a(n) = A064989(A293514(n)).
Other identities. For all n >= 1:
1 + A001222(a(n)) = A046951(n).
PROG
(PARI) A293515(n) = { my(m=1, v); fordiv(n, d, if(d>1, v = valuation(n, d); if(v>1, m *= prime(v-1)))); m; };
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 11 2017
STATUS
approved