Self-convolution of row n of array T given by A026725.

Terms

a(0) =1a(1) =2a(2) =6a(3) =26a(4) =91a(5) =414a(6) =1519a(7) =6980a(8) =26176a(9) =120596a(10) =457880a(11) =2110422a(12) =8076044a(13) =37211408a(14) =143165518a(15) =659264978a(16) =2546261659a(17) =11717539646a(18) =45387607779a(19) =208729977124a(20) =810316893827