G.f. satisfies: A(x) = exp( Sum_{n>=1} [Sum_{k=0..n} C(n,k)^3 * x^k] * x^n*A(x)^n/n ).
A199875
G.f. satisfies: A(x) = exp( Sum_{n>=1} [Sum_{k=0..n} C(n,k)^3 * x^k] * x^n*A(x)^n/n ).
Terms
- a(0) =1a(1) =1a(2) =3a(3) =12a(4) =51a(5) =233a(6) =1126a(7) =5639a(8) =29001a(9) =152364a(10) =814268a(11) =4412733a(12) =24193883a(13) =133964582a(14) =748084930a(15) =4208233719a(16) =23825366565a(17) =135657095301a(18) =776310257573
External references
- oeis: A199875