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A272404 Primes p == 1 (mod 3) for which A261029(26*p) = 3. 7
7, 19, 31, 37, 43, 61, 67, 73, 79, 97, 103, 109, 127, 139, 151, 157, 163, 181, 193, 199, 223, 241, 277, 349, 463, 601 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

By theorem in A272382, case q=13, the sequence is finite with a(n) <= 676.

LINKS

Table of n, a(n) for n=1..26.

Vladimir Shevelev, Representation of positive integers by the form x^3+y^3+z^3-3xyz, arXiv:1508.05748 [math.NT], 2015.

MATHEMATICA

r[n_] := Reduce[0 <= x <= y <= z && z >= x + 1 && n == x^3 + y^3 + z^3 - 3 x y z, {x, y, z}, Integers];

a29[n_] := Which[rn = r[n]; rn === False, 0, rn[[0]] === And, 1, rn[[0]] === Or, Length[rn], True, Print["error ", rn]];

Select[Range[1, 997, 3], PrimeQ[#] && a29[26#] == 3&] (* Jean-Fran├žois Alcover, Nov 06 2018 *)

CROSSREFS

Cf. A261029, A272381, A272382, A272384.

Sequence in context: A122072 A261338 A109355 * A274971 A040045 A242476

Adjacent sequences:  A272401 A272402 A272403 * A272405 A272406 A272407

KEYWORD

nonn,fini,full

AUTHOR

Vladimir Shevelev, Apr 29 2016

EXTENSIONS

All terms (after first author's ones) were calculated by Peter J. C. Moses, Apr 29 2016

STATUS

approved

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Last modified September 23 20:42 EDT 2021. Contains 347617 sequences. (Running on oeis4.)