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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.

A098505 Numerators in inverse of a Catalan scaled binomial matrix.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 3, 3, 1, 1, 2, 3, 2, 1, 1, 5, 5, 5, 5, 1, 1, 1, 5, 5, 5, 1, 1, 1, 7, 7, 35, 35, 7, 7, 1, 1, 4, 14, 28, 7, 28, 14, 4, 1, 1, 9, 18, 42, 63, 63, 42, 18, 9, 1, 1, 5, 45, 30, 105, 63, 105, 30, 45, 5, 1, 1, 11, 55, 165, 165, 33, 33, 165, 165, 55, 11, 1, 1, 3, 33, 55, 495, 198
Offset: 0

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Author

Paul Barry, Sep 11 2004

Keywords

Comments

Row sums are A098506. Diagonal sums are A098507. Second column is A093527. Third column is A098508. Numerators in the inverse of the signed version of A098474, defined by T(n,k)=(-1)^(n-k)binomial(2k,k)binomial(n,k)/(k+1)

Examples

			Rows begin:
  1;
  1,1;
  1,1,1;
  1,3,3,1;
  1,2,3,2,1;
  1,5,5,5,5,1;
  ...
		

Crossrefs

Programs

  • Mathematica
    Table[Numerator[(n + 1)*Binomial[n, k]/Binomial[2*n, n]], {n, 0, 15}, {k, 0, n}] (* Paolo Xausa, Aug 30 2024 *)

Formula

T(n, k) = numerator((n+1)*binomial(n, k)/binomial(2n, n)).