Expansion of (1+x-x^2)/((1-x)*(1-4*x^2)).

Terms

a(0) =1a(1) =2a(2) =5a(3) =9a(4) =21a(5) =37a(6) =85a(7) =149a(8) =341a(9) =597a(10) =1365a(11) =2389a(12) =5461a(13) =9557a(14) =21845a(15) =38229a(16) =87381a(17) =152917a(18) =349525a(19) =611669a(20) =1398101a(21) =2446677a(22) =5592405a(23) =9786709a(24) =22369621a(25) =39146837a(26) =89478485a(27) =156587349a(28) =357913941a(29) =626349397