E.g.f.: exp(Sum_{n>=1} A000009(n)*x^n/n).

Terms

a(0) =1a(1) =1a(2) =2a(3) =8a(4) =38a(5) =238a(6) =1828a(7) =16096a(8) =160604a(9) =1826684a(10) =23018264a(11) =316422304a(12) =4755059848a(13) =77084268712