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.

A091623 Column 1 of triangle A091614.

Original entry on oeis.org

1, -1, -3, -1, 5, 13, 27, 41, 43, 25, -23, -157, -447, -1011, -2087, -4081, -7685, -14141, -25707, -46251, -82729, -147295, -261317, -462403, -816653, -1439457, -2532779, -4448035, -7794637, -13624815, -23744693, -41230561, -71277787
Offset: 1

Views

Author

Christian G. Bower, Jan 23 2004

Keywords

Crossrefs

Cf. A091614.

Programs

  • Mathematica
    b[n_, l_, k_]:= b[n, l, k]= If[n==0, 1, Sum[If[i==l, 0, Sum[b[n-i*j, i, k], {j, 1, Min[k, n/i]}]], {i, n}]];
    t[n_, k_]:= t[n, k]= If[k>n, 0, b[n, 0, k] - b[n, 0, k-1]]; (* A091613 *)
    M:= With[{p=53}, Table[t[n, k], {n, p}, {k, p}]];
    T := Inverse[M]; (* A091614 *)
    Table[T[[n, 1]], {n, 50}] (* G. C. Greubel, Nov 27 2021 *)