a(1)=a(2)=1. For n >= 3, a(n) = (product{k=1 to n-1} a(k)) - (sum{j=1 to n-1} a(j)).
A123702
a(1)=a(2)=1. For n >= 3, a(n) = (product{k=1 to n-1} a(k)) - (sum{j=1 to n-1} a(j)).
Terms
- a(0) =1a(1) =1a(2) =-1a(3) =-2a(4) =3a(5) =4a(6) =18a(7) =408a(8) =175824a(9) =30989858688
External references
- oeis: A123702