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

Terms

a(0) =1a(1) =9a(2) =51a(3) =234a(4) =951a(5) =3573a(6) =12707a(7) =43398a(8) =143682a(9) =464148a(10) =1469778a(11) =4578102a(12) =14063653a(13) =42695127a(14) =128301453a(15) =382144446a(16) =1129360689a(17) =3314619171a(18) =9668400839a(19) =28045947996a(20) =80949547380a(21) =232589050920a(22) =665532883380