Expansion of (1-x)^2*(1-3*x)/(1-9*x+28*x^2-35*x^3+15*x^4-x^5).

Terms

a(0) =1a(1) =4a(2) =15a(3) =55a(4) =200a(5) =726a(6) =2638a(7) =9604a(8) =35037a(9) =128061a(10) =468809a(11) =1718446a(12) =6305546a(13) =23155863a(14) =85089015a(15) =312823200a(16) =1150506841a(17) =4232595095a(18) =15574796945a(19) =57320990295a(20) =210990647105a(21) =776707569176