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A112818
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Numbers k such that lcm(1,2,3,...,k)/13 equals the denominator of the k-th harmonic number H(k).
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12
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156, 157, 158, 159, 160, 161, 27380, 27381, 27382, 27383, 27384, 27385, 27386, 27387, 27388, 27389, 27390, 27391, 27392, 27393, 27394, 27395, 27396, 27397, 27398, 27399, 27400, 27401, 27402, 27403, 27404, 27405, 27406, 27407, 27408
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OFFSET
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1,1
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COMMENTS
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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; b = a/Denominator[h]; If[b == 13, AppendTo[t, n]], {n, 27408}]; t
With[{tk=Table[{LCM@@Range[k]/13, Denominator[HarmonicNumber[k]]}, {k, 28000}]}, Position[ tk, _?(#[[1]]==#[[2]]&), 1, Heads->False]]//Flatten (* Harvey P. Dale, Apr 02 2022 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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