Expansion of Sum_{k>=0} (x^2 / (1 - k*x))^k.

Terms

a(0) =1a(1) =0a(2) =1a(3) =1a(4) =2a(5) =5a(6) =14a(7) =42a(8) =136a(9) =479a(10) =1825a(11) =7433a(12) =32053a(13) =145608a(14) =695081a(15) =3479117a(16) =18209842a(17) =99373513a(18) =563920590a(19) =3320674902a(20) =20255823092a(21) =127799984935a(22) =832807892861