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.

A203680 v(n+1)/v(n), where v=A203679.

Original entry on oeis.org

7, 588, 686784, 11999490048, 3246966011068416, 13834880585785015271424, 935753249231126352597092401152, 1008697565620854720371433477717910093824, 17363204603463390874081663579386879116150726197248
Offset: 1

Views

Author

Clark Kimberling, Jan 04 2012

Keywords

Comments

See A093883 for a discussion and guide to related sequences.

Programs

  • Mathematica
    f[j_] := 2^(j - 1); z = 12;
    u[n_] := Product[f[j]^2 + f[j] f[k] + f[k]^2, {j, 1, k - 1}]
    v[n_] := Product[u[n], {k, 2, n}]
    Table[v[n], {n, 1, z}]          (* A203679 *)
    Table[v[n + 1]/v[n], {n, 1, z}] (* A203680 *)