G.f.: Sum_{n>=0} x^n*Product_{k=1..n} (1 - k*x) / (1 - (2*k)*x).
A193321
G.f.: Sum_{n>=0} x^n*Product_{k=1..n} (1 - k*x) / (1 - (2*k)*x).
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =23a(5) =106a(6) =565a(7) =3391a(8) =22523a(9) =163578a(10) =1286990a(11) =10886149a(12) =98377648a(13) =944863003a(14) =9602092037a(15) =102856190049
External references
- oeis: A193321