G.f. A(x) satisfies: A(x) = 1 + x*(1 + x*A(x/(1 - x)^2)/(1 - x)^2).
A307875
G.f. A(x) satisfies: A(x) = 1 + x*(1 + x*A(x/(1 - x)^2)/(1 - x)^2).
Terms
- a(0) =1a(1) =1a(2) =1a(3) =3a(4) =8a(5) =23a(6) =78a(7) =308a(8) =1343a(9) =6288a(10) =31520a(11) =169556a(12) =976219a(13) =5974381a(14) =38597158a(15) =262016556a(16) =1864047379a(17) =13870571346a(18) =107732190252a(19) =871392244426
External references
- oeis: A307875