a(n) = coefficient of x^n, n >= 1, in A(x) such that: A(x)^2 = A( x^2/(1 - 4*x - 4*x^2) ) * sqrt(1 - 4*x - 4*x^2).
A357785
a(n) = coefficient of x^n, n >= 1, in A(x) such that: A(x)^2 = A( x^2/(1 - 4*x - 4*x^2) ) * sqrt(1 - 4*x - 4*x^2).
Terms
- a(0) =1a(1) =1a(2) =4a(3) =15a(4) =65a(5) =291a(6) =1356a(7) =6474a(8) =31555a(9) =156315a(10) =784924a(11) =3986534a(12) =20444676a(13) =105728100a(14) =550735400a(15) =2886924190a(16) =15217019595a(17) =80600822575a(18) =428766983300
External references
- oeis: A357785