G.f.: A(x) = 1 + x*A(x)^2 / ( A(w*x)*A(w^2*x) ), where w = exp(2*Pi*I/3).
A216713
G.f.: A(x) = 1 + x*A(x)^2 / ( A(w*x)*A(w^2*x) ), where w = exp(2*Pi*I/3).
Terms
- a(0) =1a(1) =1a(2) =3a(3) =12a(4) =27a(5) =105a(6) =420a(7) =1242a(8) =5295a(9) =22395a(10) =72738a(11) =323268a(12) =1410684a(13) =4806675a(14) =21881721a(15) =97371786a(16) =341608239a(17) =1579726122a(18) =7123796790a(19) =25489388367a(20) =119184247992a(21) =542664427242
External references
- oeis: A216713