Triangle read by rows: T(n,k) is the number of 2-compositions of n having k 0's in the top row A 2-composition of n is a nonnegative matrix with two rows, such that each column has at least one nonzero entry and whose entries sum up to n.
A181330
Triangle read by rows: T(n,k) is the number of 2-compositions of n having k 0's in the top row A 2-composition of n is a nonnegative matrix with two rows, such that each column has at least one nonzero entry and whose entries sum up to n.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =3a(4) =3a(5) =1a(6) =8a(7) =10a(8) =5a(9) =1a(10) =21a(11) =32a(12) =21a(13) =7a(14) =1a(15) =55a(16) =99a(17) =80a(18) =36a(19) =9a(20) =1a(21) =144a(22) =299a(23) =286a(24) =160a(25) =55a(26) =11a(27) =1a(28) =377a(29) =887
External references
- oeis: A181330