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.

A203529 a(n) = A203527(n)/A000178(n-1); A000178 = (superfactorials).

Original entry on oeis.org

1, 5, 175, 44100, 60913125, 427756329000, 20552836095792000, 6952965728817588480000, 11895516181976215338950400000, 99606443887767729350960121600000000, 5830034964946921746536425070101217280000000
Offset: 1

Views

Author

Clark Kimberling, Jan 03 2012

Keywords

Comments

It is conjectured that every term is an integer.

Crossrefs

Programs

  • Mathematica
    t = Table[If[PrimeQ[k], 0, k], {k, 1, 100}];
    nonprime = Rest[Union[t]]              (* A018252 *)
    f[j_] := nonprime[[j]]; z = 20;
    v[n_] := Product[Product[f[k] + f[j], {j, 1, k - 1}], {k, 2, n}]
    d[n_] := Product[(i - 1)!, {i, 1, n}]  (* A000178 *)
    Table[v[n], {n, 1, z}]                 (* A203527 *)
    Table[v[n + 1]/v[n], {n, 1, z - 1}]    (* A203528 *)
    Table[v[n]/d[n], {n, 1, 20}]           (* A203529 *)