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A069082
Numbers n such that sigma(n)/tau(n) has denominator 3.
1
4, 9, 12, 25, 28, 52, 63, 75, 76, 84, 108, 117, 121, 124, 148, 156, 171, 172, 175, 180, 196, 228, 243, 244, 268, 279, 289, 292, 316, 325, 333, 363, 364, 372, 387, 388, 396, 412, 436, 441, 444, 475, 508, 516, 525, 529, 532, 549, 556, 588, 603, 604, 628, 652
OFFSET
1,1
COMMENTS
Numbers such that the denominator of the fraction (sum of the divisors of n) divided by (the number of divisors of n) equals 3. - Harvey P. Dale, Jul 13 2012
LINKS
FORMULA
n such that A057021(n)=3.
MATHEMATICA
Select[Range[700], Denominator[DivisorSigma[1, #]/DivisorSigma[0, #]] == 3&] (* Harvey P. Dale, Jul 13 2012 *)
PROG
(Magma) [n:n in [1..700]|Denominator(SumOfDivisors(n)/#Divisors(n)) eq 3]; // Marius A. Burtea, Sep 08 2019
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Apr 05 2002
STATUS
approved