a(n) = Sum_{m=0..n} (-1)^m * binomial(n,m)*(1*3*5*...*(4m-1)).
A102188
a(n) = Sum_{m=0..n} (-1)^m * binomial(n,m)*(1*3*5*...*(4m-1)).
Terms
- a(0) =1a(1) =-2a(2) =100a(3) =-10088a(4) =1986064a(5) =-644696864a(6) =312335967808
External references
- oeis: A102188