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Revision History for A127046

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Showing entries 1-10 | older changes
Primes p such that denominator of Sum_{k=1..p-1} 1/k^3 is a cube.
(history; published version)
#12 by Andrey Zabolotskiy at Wed Jan 03 07:18:28 EST 2024
STATUS

editing

approved

#11 by Andrey Zabolotskiy at Wed Jan 03 07:18:26 EST 2024
NAME

Primes p such that denominator of Sum_{k=1..p-1} 1/k^3} is a cube.

STATUS

approved

editing

#10 by N. J. A. Sloane at Tue May 23 21:01:59 EDT 2017
STATUS

proposed

approved

#9 by Chai Wah Wu at Tue May 23 19:49:45 EDT 2017
STATUS

editing

proposed

#8 by Chai Wah Wu at Tue May 23 19:49:33 EDT 2017
LINKS

Chai Wah Wu, <a href="/A127046/b127046.txt">Table of n, a(n) for n = 1..10000</a>

STATUS

approved

editing

#7 by T. D. Noe at Wed Mar 13 21:25:41 EDT 2013
STATUS

editing

approved

#6 by T. D. Noe at Wed Mar 13 21:25:37 EDT 2013
MAPLE

d[n_] := Module[{}, su = 0; a = {}; For[i = 1, i <= n, i++, su = su + 1/ i^3; If[PrimeQ[i + 1], If[IntegerQ[(Denominator[su])^(1/3)], AppendTo[a, i + 1]]]]; a] d[10000]

MATHEMATICA

d[n_] := Module[{}, su = 0; a = {}; For[i = 1, i <= n, i++, su = su + 1/ i^3; If[PrimeQ[i + 1], If[IntegerQ[(Denominator[su])^(1/3)], AppendTo[a, i + 1]]]]; a]; d[2000]

Select[Prime[Range[200]], IntegerQ[Surd[Denominator[Sum[1/k^3, {k, #-1}]], 3]]&] (* Harvey P. Dale, Mar 13 2013 *)

STATUS

reviewed

editing

#5 by Harvey P. Dale at Wed Mar 13 18:00:35 EDT 2013
STATUS

proposed

reviewed

#4 by Harvey P. Dale at Wed Mar 13 18:00:29 EDT 2013
STATUS

editing

proposed

#3 by Harvey P. Dale at Wed Mar 13 17:59:45 EDT 2013
MATHEMATICA

Select[Prime[Range[200]], IntegerQ[Surd[Denominator[Sum[1/k^3, {k, #-1}]], 3]]&] (* Harvey P. Dale, Mar 13 2013 *)

STATUS

approved

editing

Discussion
Wed Mar 13
18:00
Harvey P. Dale: I'm fairly certain that the Maple program is actually a Mma program, in which case it should be moved to the proper field.