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 A074692 1 + n-th prime is harmonic. 0
 3, 34, 57, 259, 428, 806, 15797, 21020, 21395, 116943, 168850, 180159, 329868, 398229, 416148, 1000579, 1453492, 2263664, 3121796, 3366944, 4077320, 5239439, 6334640, 10644940, 15607405, 22504931, 26354609, 27675237, 35041357, 42370771, 46031750, 63585017, 67747753 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..33. EXAMPLE 1 + prime(34) = 140, which is harmonic, so 34 belongs to the sequence. MATHEMATICA isHarmonic[n_] := IntegerQ[n*DivisorSigma[0, n] / DivisorSigma[1, n]]; Select[Range[10^5], isHarmonic[Prime[ # ] + 1] &] CROSSREFS Cf. A001599. Sequence in context: A197220 A042821 A110070 * A003348 A344641 A086488 Adjacent sequences: A074689 A074690 A074691 * A074693 A074694 A074695 KEYWORD easy,nonn AUTHOR Joseph L. Pe, Sep 27 2002 EXTENSIONS More terms from Amiram Eldar, Mar 24 2019 STATUS approved

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Last modified September 22 11:31 EDT 2023. Contains 365526 sequences. (Running on oeis4.)