A123597 Primes of the form p^3 + q^3 + r^3, where p, q and r are primes.
43, 179, 277, 359, 397, 593, 811, 1483, 2017, 2213, 2251, 2447, 2689, 4421, 4519, 4967, 5381, 6271, 7109, 7229, 9181, 9521, 10169, 11897, 12853, 13103, 13841, 14489, 16561, 17107, 20357, 24443, 24677, 25747, 26711, 27917, 30161, 30259, 31193, 31247, 32579, 36161
Offset: 1
Keywords
Examples
a(1) = 43 because 43 = 2^3 + 2^3 + 3^3 is prime and 2^3 + 2^3 + 2^3 = 24 is composite.
Crossrefs
Cf. A007490 = Primes of form x^3 + y^3 + z^3.
Programs
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Mathematica
lst={};Do[Do[Do[p=n^3+m^3+k^3;If[PrimeQ[p]&&PrimeQ[n]&&PrimeQ[m]&&PrimeQ[k],AppendTo[lst,p]],{n,4!}],{m,4!}],{k,4!}];Take[Union[lst],16] (* Vladimir Joseph Stephan Orlovsky, May 23 2009 *) With[{nn=40},Select[Total/@Tuples[Prime[Range[nn]]^3,3],PrimeQ[#]&<= nn^3+ 16&]]//Union (* Harvey P. Dale, Sep 08 2021 *)
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