A119364 Central coefficients of number triangle A119335.

0, 1, 1, 1, 11, 81, 351, 1149, 3529, 12601, 52724, 222641, 879308, 3295384, 12303201, 47320365, 186738507, 739129809, 2894481813, 11237844615, 43647142533, 170543919327, 669744238998, 2633027605209, 10337488816041, 40544676533466

Offset: 0

Author

Paul Barry, May 16 2006

Keywords

• easy
• nonn

Comments

A119363(n)-a(n)=A119365(n).

Formula

a(n)=sum{k=0..n-1, C(n+1,3k)*C(n-1,3k)}; a(n)=A119335(2n,n+1).