G.f. A(x) satisfies A(x) = 1/( 1 - x*(A(x) + A(-x))*(A(x) + A(w*x) + A(w^2*x))/6 ), where w = exp(2*Pi*i/3).
A385699
G.f. A(x) satisfies A(x) = 1/( 1 - x*(A(x) + A(-x))*(A(x) + A(w*x) + A(w^2*x))/6 ), where w = exp(2*Pi*i/3).
Terms
- a(0) =1a(1) =1a(2) =1a(3) =2a(4) =5a(5) =13a(6) =24a(7) =88a(8) =181a(9) =523a(10) =1616a(11) =4891a(12) =10540a(13) =42009a(14) =94953a(15) =294102a(16) =957259a(17) =3028320a(18) =6864540a(19) =28208447a(20) =66180997a(21) =211105506a(22) =703497178a(23) =2273009790a(24) =5283518340a(25) =22058432677a(26) =52795736539a(27) =171169636087a(28) =578132050147
External references
- oeis: A385699