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.

A035248 Indices of nonzero terms in expansion of Dirichlet series Product_p (1-(Kronecker(m,p)+1)*p^(-s)+Kronecker(m,p)*p^(-2s))^(-1) for m= -7 (A035182).

Original entry on oeis.org

1, 2, 4, 7, 8, 9, 11, 14, 16, 18, 22, 23, 25, 28, 29, 32, 36, 37, 43, 44, 46, 49, 50, 53, 56, 58, 63, 64, 67, 71, 72, 74, 77, 79, 81, 86, 88, 92, 98, 99, 100, 106, 107, 109, 112, 113, 116, 121, 126, 127, 128, 134, 137, 142, 144, 148, 149, 151, 154, 158, 161, 162, 163, 169, 172, 175
Offset: 1

Views

Author

Keywords

Comments

Is this A028951 with the initial 0 dropped? [Joerg Arndt, Dec 08 2013]

Crossrefs

Cf. A028951. [From R. J. Mathar, Oct 20 2008]
Cf. A035182 (Expansion for m= -7).

Programs

  • Mathematica
    Reap[For[n = 1, n < 200, n++, r = Reduce[x^2 + x y + 2 y^2 == n, {x, y}, Integers]; If[r =!= False, Sow[n]]]][[2, 1]] (* Jean-François Alcover, Oct 31 2016 *)
  • PARI
    m=-7; v=direuler(p=2, 301, 1/(1-(kronecker(m, p)*(X-X^2))-X));
    for(j=1,#v,if(v[j],print1(j,", ")));

Extensions

Added more terms, Joerg Arndt, Dec 08 2013
Definition corrected by Georg Fischer, Sep 03 2020