G.f. A(x) satisfies: A(x) = A(x^2 + 2*x^3) / x.

Terms

a(0) =1a(1) =2a(2) =2a(3) =8a(4) =10a(5) =12a(6) =32a(7) =80a(8) =202a(9) =356a(10) =540a(11) =944a(12) =1552a(13) =2688a(14) =5648a(15) =12544a(16) =27850a(17) =60980a(18) =133380a(19) =290320a(20) =615212a(21) =1250024a(22) =2422336a(23) =4537056a(24) =8352016a(25) =15256736a(26) =28031232a(27) =52183296a(28) =97737488a(29) =182819808