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A112821
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Numbers n such that lcm(1,2,3,...,n)/19 equals the denominator of the n-th harmonic number H(n).
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11
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343, 344, 345, 346, 347, 348, 349, 350, 351, 352, 353, 354, 355, 356, 357, 358, 359, 360
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OFFSET
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1,1
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COMMENTS
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Positions where 19 occurs in A110566.
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LINKS
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MATHEMATICA
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a = h = 1; t = {}; Do[a = LCM[a, n]; h = h + 1/n; If[a/Denominator[h] == 19, AppendTo[t, n]], {n, 10^6}]; t
Select[Range[500], Denominator[HarmonicNumber[#]]==LCM@@Range[#]/19&] (* Harvey P. Dale, Jan 29 2012 *)
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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