a(n) = [x^n] ((Sum_{k=0..n} (k+3)!*x^k)/(Sum_{k=0..n} (k+3)!*(-x)^k))^(1/4).
A303568
a(n) = [x^n] ((Sum_{k=0..n} (k+3)!*x^k)/(Sum_{k=0..n} (k+3)!*(-x)^k))^(1/4).
Terms
- a(0) =1a(1) =2a(2) =2a(3) =32a(4) =62a(5) =1764a(6) =3916a(7) =173376a(8) =393446a(9) =25166076a(10) =56406348a(11) =4958003840a(12) =10882283500
External references
- oeis: A303568