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 A227108 Denominators of harmonic mean H(n,5), n >= 0. 2
 1, 3, 7, 4, 9, 1, 11, 6, 13, 7, 3, 8, 17, 9, 19, 2, 21, 11, 23, 12, 1, 13, 27, 14, 29, 3, 31, 16, 33, 17, 7, 18, 37, 19, 39, 4, 41, 21, 43, 22, 9, 23, 47, 24, 49, 1, 51, 26, 53, 27, 11, 28, 57, 29, 59, 6, 61, 31, 63, 32, 13, 33, 67, 34, 69, 7, 71, 36, 73, 37, 3, 38, 77 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS a(n) = denominator(H(n,5)) = denominator(10*n/(n+5)), n>=0, with H(n,5) the harmonic mean of n and 5. The corresponding numerators are given in A227109(n), n >= 0. a(n+5), n>=0, is the fifth column (m=5) of the triangle A227042. LINKS FORMULA a(n) = denominator(10*n/(n+5)), n >= 0. a(n) = (n+m)/gcd(n+5, 10*n) = (n+5)/gcd(n+5, 50), n >= 0. EXAMPLE The rationals H(n,5) begin: 0, 5/3, 20/7, 15/4, 40/9, 5, 60/11, 35/6, 80/13, 45/7, 20/3, 55/8, 120/17, 65/9, ... CROSSREFS Cf. A227042(n+5,5), A227109 (numerators). Sequence in context: A274511 A179706 A231325 * A016619 A066538 A216627 Adjacent sequences:  A227105 A227106 A227107 * A227109 A227110 A227111 KEYWORD nonn,frac,easy AUTHOR Wolfdieter Lang, Jul 01 2013 STATUS approved

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Last modified December 12 15:11 EST 2019. Contains 329960 sequences. (Running on oeis4.)