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 A112815 Numbers k such that lcm(1,2,3,...,k)/7 equals the denominator of the k-th harmonic number H(k). 12
 44, 45, 46, 47, 48, 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320, 321, 322, 323, 324, 325, 326, 327, 328, 329, 330, 331, 332, 333, 334, 335, 2209, 2210, 2211, 2212, 2213, 2214, 2215, 2216, 2217, 2218, 2219 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS When 7 occurs in A110566. LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 MATHEMATICA f[n_] := LCM @@ Range[n]/Denominator[ HarmonicNumber[n]]; Select[ Range[2219], f[ # ] == 7 &] PROG (PARI) isok(n) = lcm(vector(n, i, i)) == 7*denominator(sum(i=1, n, 1/i)); \\ Michel Marcus, Mar 07 2018 CROSSREFS Cf. A002805, A003418, A110566. Cf. A098464, A112813, A112814, A112816, A112817, A112818, A112819, A112820, A112821, A112822. Sequence in context: A059070 A059071 A085519 * A242934 A038400 A254750 Adjacent sequences:  A112812 A112813 A112814 * A112816 A112817 A112818 KEYWORD nonn AUTHOR Robert G. Wilson v, Sep 17 2005 STATUS approved

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Last modified September 20 16:50 EDT 2021. Contains 347586 sequences. (Running on oeis4.)