a(n) = T(6,n), array T given by A048472.

Terms

a(0) =1a(1) =8a(2) =29a(3) =85a(4) =225a(5) =561a(6) =1345a(7) =3137a(8) =7169a(9) =16129a(10) =35841a(11) =78849a(12) =172033a(13) =372737a(14) =802817a(15) =1720321a(16) =3670017a(17) =7798785a(18) =16515073a(19) =34865153a(20) =73400321a(21) =154140673a(22) =322961409a(23) =675282945a(24) =1409286145a(25) =2936012801a(26) =6106906625a(27) =12683575297a(28) =26306674689a(29) =54492397569