Main diagonal of triangle A097094; g.f. A(x) satisfies A(x)/(1-x-x^2) = A(x^2)^2/(1-x-x^3)^2.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =7a(5) =8a(6) =15a(7) =19a(8) =37a(9) =42a(10) =66a(11) =76a(12) =122a(13) =114a(14) =148a(15) =90a(16) =77a(17) =-213a(18) =-574a(19) =-1511a(20) =-2860a(21) =-5773a(22) =-10209a(23) =-18310a(24) =-30884a(25) =-52778a(26) =-87051a(27) =-143621a(28) =-232157a(29) =-375464