Catalan's triangle T(n,k) (read by rows): each term is the sum of the entries above and to the left, i.e., T(n,k) = Sum_{j=0..k} T(n-1,j).
A009766
Catalan's triangle T(n,k) (read by rows): each term is the sum of the entries above and to the left, i.e., T(n,k) = Sum_{j=0..k} T(n-1,j).
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =2a(6) =1a(7) =3a(8) =5a(9) =5a(10) =1a(11) =4a(12) =9a(13) =14a(14) =14a(15) =1a(16) =5a(17) =14a(18) =28a(19) =42a(20) =42a(21) =1a(22) =6a(23) =20a(24) =48a(25) =90a(26) =132a(27) =132a(28) =1a(29) =7
External references
- oeis: A009766