G.f. satisfies: A(x) = Sum_{n>=0} x^n * Sum_{k=0..n} x^k * {[x^k] A(x)^(4*n)}.
A249937
G.f. satisfies: A(x) = Sum_{n>=0} x^n * Sum_{k=0..n} x^k * {[x^k] A(x)^(4*n)}.
Terms
- a(0) =1a(1) =1a(2) =5a(3) =9a(4) =81a(5) =143a(6) =1209a(7) =2219a(8) =20321a(9) =37286a(10) =342223a(11) =633652a(12) =5909073a(13) =10982266a(14) =103012275a(15) =192218108a(16) =1813703113a(17) =3393964127a(18) =32149901302a(19) =60309293738a(20) =573151325939
External references
- oeis: A249937