Expansion of 1/(x^k*(1-x-3*x^(k+1))) for k=6.

Terms

a(0) =1a(1) =4a(2) =7a(3) =10a(4) =13a(5) =16a(6) =19a(7) =22a(8) =34a(9) =55a(10) =85a(11) =124a(12) =172a(13) =229a(14) =295a(15) =397a(16) =562a(17) =817a(18) =1189a(19) =1705a(20) =2392a(21) =3277a(22) =4468a(23) =6154a(24) =8605a(25) =12172a(26) =17287a(27) =24463a(28) =34294a(29) =47698