Triangle read by rows: T(n,k) = binomial(n-1,k-1)*binomial(n,k-1)/k + binomial(n-1,k)*binomial(n,k)/(k+1) (1 <= k <= n). In other words, to each entry of the Narayana triangle (A001263) add the entry on its right.
A118976
Triangle read by rows: T(n,k) = binomial(n-1,k-1)*binomial(n,k-1)/k + binomial(n-1,k)*binomial(n,k)/(k+1) (1 <= k <= n). In other words, to each entry of the Narayana triangle (A001263) add the entry on its right.
Terms
- a(0) =1a(1) =2a(2) =1a(3) =4a(4) =4a(5) =1a(6) =7a(7) =12a(8) =7a(9) =1a(10) =11a(11) =30a(12) =30a(13) =11a(14) =1a(15) =16a(16) =65a(17) =100a(18) =65a(19) =16a(20) =1a(21) =22a(22) =126a(23) =280a(24) =280a(25) =126a(26) =22a(27) =1a(28) =29a(29) =224
External references
- oeis: A118976