A number triangle of sums of binomial products.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =2a(8) =1a(9) =1a(10) =1a(11) =3a(12) =3a(13) =1a(14) =1a(15) =1a(16) =5a(17) =7a(18) =4a(19) =1a(20) =1a(21) =1a(22) =8a(23) =19a(24) =13a(25) =5a(26) =1a(27) =1a(28) =1a(29) =13