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 1-2 of 2 results.

A152753 Last digit of even Catalan number A152670(n).

Original entry on oeis.org

2, 4, 2, 2, 0, 2, 6, 6, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 2, 2, 4, 0, 8, 4, 8, 0, 4, 2, 2, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 6, 6, 2, 0, 4, 2, 2, 4, 0, 2, 6, 6, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
Offset: 1

Views

Author

Omar E. Pol, Dec 12 2008

Keywords

Comments

Even values of A152669.

Crossrefs

Cf. A000108, A038003, A094389, A152669, A152670.

A152671 Even Catalan numbers divided by 2.

Original entry on oeis.org

1, 7, 21, 66, 715, 2431, 8398, 29393, 104006, 371450, 1337220, 17678835, 64822395, 238819350, 883631595, 3282060210, 12233133510, 45741281820, 171529806825, 644952073662, 2430973200726, 9183676536076, 34766775458002
Offset: 1

Views

Author

Omar E. Pol, Dec 10 2008

Keywords

Crossrefs

Cf. A000108, A152670.

Programs

  • Mathematica
    Select[CatalanNumber[Range[30]], EvenQ]/2 (* Vladimir Reshetnikov, Nov 02 2015 *)
  • PARI
    lista(nn) = for (n=1, nn, if (((c=binomial(2*n,n)/(n+1)) % 2) == 0, print1(c/2, ", "))); \\ Michel Marcus, Nov 02 2015

Formula

a(n) = A152670(n)/2.
Showing 1-2 of 2 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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