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A064085
Quotient of A000225 and A064084.
3
1, 1, 1, 1, 1, 3, 1, 1, 1, 11, 1, 39, 1, 43, 151, 1, 1, 171, 1, 2255, 2359, 683, 1, 9399, 1, 2731, 1, 140911, 1, 1649373, 1, 1, 599479, 43691, 8727391, 8965359, 1, 174763, 9588151, 139090655, 1, 1649061309, 1, 572942063, 2221095391, 2796203, 1
OFFSET
1,6
COMMENTS
a(n) is equal to 1 if and only if n is a prime power; the sequence of nontrivial values of a is A064086.
LINKS
FORMULA
a(n) = A000225(n) / A064084(n).
MAPLE
a:= n-> (2^n-1)/mul(2^(i[1]^i[2])-1, i=ifactors(n)[2]):
seq(a(n), n=1..50); # Alois P. Heinz, Jun 09 2014
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jens Voß, Sep 04 2001
EXTENSIONS
More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Mar 29 2003
STATUS
approved