A098508 Second column of the inverse of a Catalan scaled binomial matrix (A098505).

0, 0, 1, 3, 3, 5, 5, 7, 14, 18, 45, 55, 33, 39, 91, 7, 4, 68, 51, 57, 19, 7, 77, 253, 23, 25, 325, 351, 27, 29, 435, 465, 248, 88, 187, 85, 45, 333, 703, 741, 39, 41, 41, 43, 473, 11, 23, 1081, 94, 98, 1225, 425, 221, 689, 477, 495, 385, 133, 551, 1711, 295, 305, 1891

Offset: 0

Author

Paul Barry, Sep 11 2004

Keywords

• easy
• nonn

Links

• Paolo Xausa, Table of n, a(n) for n = 0..10000

Crossrefs

Second column of A098505.

Programs

Mathematica

Table[Numerator[n*(n^2 - 1)/(2*Binomial[2*n, n])], {n, 0, 100}] (* Paolo Xausa, Aug 30 2024 *)

Formula

a(n) = numerator((n+1)*binomial(n, 2)/binomial(2*n, n));

a(n) = numerator((n-1)*n*(n+1)/(2*binomial(2*n, n))).