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.

Showing 1-3 of 3 results.

A072042 a(n+2) = a(n+1)*a(n)*(1+1/n), a(1)=a(2)=1.

Original entry on oeis.org

1, 1, 2, 3, 8, 30, 288, 10080, 3317760, 37623398400, 138694895861760000, 5739990655358858585702400000, 868480806755424464755519466250436608000000000
Offset: 1

Views

Author

Benoit Cloitre, Jul 29 2002

Keywords

Crossrefs

Programs

  • Mathematica
    a[1] = a[2] = 1; a[n_] := a[n - 1]*a[n - 2]*(1 + 1/(n - 2)); Table[ a[n], {n, 1, 13}]
    RecurrenceTable[{a[1]==a[2]==1,a[n+2]==a[n+1]*a[n]*(1+1/n)},a,{n,13}] (* Harvey P. Dale, Sep 18 2018 *)

Extensions

Edited by Robert G. Wilson v, Jul 31 2002

A235857 Associated with random Penrose-Robinson tilings of the plane.

Original entry on oeis.org

1, 2, 12, 1536, 519045120, 156130677884314787512320, 12538151702000091464104493325082133822247601116646227522355200
Offset: 0

Views

Author

Steven Finch, Jan 16 2014

Keywords

Comments

In the Mathematica code, let p=A235857; q=A235858 for convenience.

Crossrefs

Programs

  • Mathematica
    p[n_] := p[n] = 2 p[n-1] q[n-1] - p[n-1]^2 q[n-2];
    q[n_] := 2 p[n] q[n-1] - p[n-1] p[n-2] q[n-1] q[n-2]^2;
    p[0] = 1; q[0] = 1; p[1] = 2; q[1] = 4;

A242935 Number of forced tiles in the local empire of the eight possible vertex configurations in a Penrose rhomb tiling, in the order D, J, S, Q, S5, K, S3, S4.

Original entry on oeis.org

0, 2, 5, 10, 25, 27, 43, 99
Offset: 1

Views

Author

Felix Fröhlich, May 27 2014

Keywords

Comments

The sequence refers to Figures 3.5 - 3.11 on pp. 28-32 of Effinger-Dean's thesis. It has been decided that the numbers should be listed here in the OEIS in order of increasing size. - M. F. Hasler, Jun 04 2019

Crossrefs

Extensions

Terms reordered by M. F. Hasler, Jun 04 2019
Showing 1-3 of 3 results.