cp's OEIS Frontend

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.

A050803 Cubes expressible as the sum of two nonzero squares in at least one way.

Original entry on oeis.org

8, 125, 512, 1000, 2197, 4913, 5832, 8000, 15625, 17576, 24389, 32768, 39304, 50653, 64000, 68921, 91125, 125000, 140608, 148877, 195112, 226981, 274625, 314432, 373248, 389017, 405224, 512000, 551368, 614125, 704969, 729000, 912673, 941192
Offset: 1

Views

Author

Patrick De Geest, Sep 15 1999

Keywords

Comments

Root values equal terms from sequence A000404 'Sum of 2 nonzero squares'.
In other words, a(n)=(A000404(n))^3. - Artur Jasinski, Nov 29 2007
Obviously, if n and m are different members of this sequence, then n*m is also a member of this sequence. Additionally, if k^3 is a member of this sequence and k is not in A050804, then k^6 is also a member of this sequence. - Altug Alkan, May 11 2016

Examples

			551368 or 82^3 = 82^2 + 738^2 = 242^2 + 702^2.
		

References

  • Ian Stewart, "Game, Set and Math", Chapter 8 'Close Encounters of the Fermat Kind', Penguin Books, Ed. 1991, pp. 107-124.

Crossrefs

Programs

  • Mathematica
    a[n_]:=Module[{c=0},i=1; While[i^2Jayanta Basu, May 30 2013 *)
    Select[Range[100]^3, Length[DeleteCases[PowersRepresentations[#, 2, 2], w_ /; MemberQ[w, 0]]] > 0 &] (* Michael De Vlieger, May 11 2016 *)

Extensions

Edited by N. J. A. Sloane, May 15 2008 at the suggestion of R. J. Mathar