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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A088241 Values of y, where x^2 + xy + y^2 = p (xA002476).

Original entry on oeis.org

2, 3, 3, 5, 4, 6, 5, 7, 8, 7, 8, 9, 7, 7, 10, 9, 12, 11, 11, 9, 13, 14, 11, 12, 15, 10, 12, 13, 17, 16, 11, 13, 17, 13, 17, 15, 12, 15, 20, 13, 18, 17, 21, 21, 18, 17, 21, 14, 21, 19, 24, 23, 19, 22, 15, 18, 20, 21, 19, 25, 18, 19, 23, 21, 27, 17, 27, 25, 19, 20, 27, 23, 28, 21, 26
Offset: 1

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Author

Lekraj Beedassy, Nov 03 2003

Keywords

Crossrefs

Programs

  • Maple
    R:= NULL: count:= 0:
    for k from 1 while count < 100 do
      p:= 6*k+1;
      if not isprime(p) then next fi;
      S:= select(t -> subs(t,x) > 0 and subs(t,x) < subs(t,y), [isolve(x^2+x*y+y^2=p)]);
      S:= map(t -> subs(t,y), S);
      R:= R,op(S); count:= count+1;
    od:
    R; #Robert Israel, Jun 16 2025
  • Mathematica
    Reap[For[n = 1, n <= 200, n++, If[PrimeQ[p = 6 n + 1], s = Solve[x^2 + x y + y^2 == p && 0 < x < y, {x, y}, Integers]; Sow[y /. s[[1]]]]]][[2, 1]] (* Jean-François Alcover, Mar 07 2020 *)

Extensions

More terms from Ray Chandler, Nov 04 2003