Expansion of g.f. 5*(1-x-x^2)/((1+x)*(1-3*x+x^2)).

Terms

a(0) =5a(1) =5a(2) =15a(3) =35a(4) =95a(5) =245a(6) =645a(7) =1685a(8) =4415a(9) =11555a(10) =30255a(11) =79205a(12) =207365a(13) =542885a(14) =1421295a(15) =3720995a(16) =9741695a(17) =25504085a(18) =66770565a(19) =174807605a(20) =457652255a(21) =1198149155a(22) =3136795215a(23) =8212236485a(24) =21499914245a(25) =56287506245a(26) =147362604495a(27) =385800307235