T(n,0) + T(n,1) + ... + T(n,n), T given by A026648.

Terms

a(0) =1a(1) =2a(2) =5a(3) =10a(4) =22a(5) =44a(6) =98a(7) =196a(8) =436a(9) =872a(10) =1940a(11) =3880a(12) =8632a(13) =17264a(14) =38408a(15) =76816a(16) =170896a(17) =341792a(18) =760400a(19) =1520800a(20) =3383392a(21) =6766784a(22) =15054368a(23) =30108736a(24) =66984256a(25) =133968512a(26) =298045760a(27) =596091520a(28) =1326151552a(29) =2652303104