Expansion of g.f. x/((1-x)*(1-3*x+2*x^2-x^3)).

Terms

a(0) =1a(1) =4a(2) =11a(3) =27a(4) =64a(5) =150a(6) =350a(7) =815a(8) =1896a(9) =4409a(10) =10251a(11) =23832a(12) =55404a(13) =128800a(14) =299425a(15) =696080a(16) =1618191a(17) =3761839a(18) =8745216a(19) =20330162a(20) =47261894a(21) =109870575a(22) =255418100a(23) =593775045a(24) =1380359511a(25) =3208946544a(26) =7459895656a(27) =17342153392a(28) =40315615409a(29) =93722435100