Diagonal sums of a Krawtchouk triangle.

Terms

a(0) =1a(1) =1a(2) =0a(3) =1a(4) =5a(5) =6a(6) =3a(7) =13a(8) =42a(9) =55a(10) =55a(11) =162a(12) =413a(13) =591a(14) =810a(15) =2001a(16) =4451a(17) =6900a(18) =11091a(19) =24795a(20) =51030a(21) =84337a(22) =147253a(23) =309666a(24) =610695a(25) =1058041a(26) =1928646a(27) =3903175a(28) =7528741a(29) =13480380