Self-convolution of row n of array T given by A026736.

Terms

a(0) =1a(1) =2a(2) =6a(3) =20a(4) =78a(5) =282a(6) =1187a(7) =4428a(8) =19175a(9) =72820a(10) =319493a(11) =1227712a(12) =5424359a(13) =21018514a(14) =93252862a(15) =363563668a(16) =1617342486a(17) =6334904252a(18) =28232695584a(19) =110982722888a(20) =495257577162