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A127049
Primes p such that denominator of Sum_{k=1..p-1} 1/k^6 is a sixth power.
5
2, 3, 5, 7, 17, 19, 41, 43, 47, 97, 127, 191, 193, 197, 199, 211, 223, 227, 229, 739, 743, 751, 757, 761, 769, 773, 787, 797, 809, 811, 991, 997, 1009, 1013, 1187, 1193, 1201, 3167, 3169, 3181, 3187, 3191, 3203, 3209, 3217, 3221, 3229, 3613, 3617, 3623, 3631
OFFSET
1,1
LINKS
MATHEMATICA
d[n_] := Module[{}, su = 0; a = {}; For[i = 1, i <= n, i++, su = su + 1/ i^6; If[PrimeQ[i + 1] && IntegerQ[(Denominator[su])^(1/6)], AppendTo[a, i + 1]]]; a]; d[2000]
Select[Prime[Range[600]], IntegerQ[Surd[Denominator[Sum[1/k^6, {k, #-1}]], 6]]&] (* Harvey P. Dale, Aug 04 2019 *)
KEYWORD
nonn
AUTHOR
Artur Jasinski, Jan 03 2007, Jan 04 2007
EXTENSIONS
Edited by N. J. A. Sloane, Jul 03 2008 at the suggestion of R. J. Mathar
STATUS
approved