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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 (list; graph; refs; listen; history; text; internal format)
 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 Amiram Eldar, Table of n, a(n) for n = 1..10000 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 Cf. A000005, A000203, A057021. Sequence in context: A199973 A320925 A212875 * A344415 A297414 A076794 Adjacent sequences:  A069079 A069080 A069081 * A069083 A069084 A069085 KEYWORD easy,nonn AUTHOR Benoit Cloitre, Apr 05 2002 STATUS approved

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Last modified May 20 01:04 EDT 2022. Contains 353847 sequences. (Running on oeis4.)