a(0)=0, a(1)=1; a(n) = n*a(n-1) + (n-2)*a(n-2) - Sum_{j=1..n-1} a(j)*a(n-j).
A259870
a(0)=0, a(1)=1; a(n) = n*a(n-1) + (n-2)*a(n-2) - Sum_{j=1..n-1} a(j)*a(n-j).
Terms
- a(0) =0a(1) =1a(2) =1a(3) =2a(4) =5a(5) =17a(6) =74a(7) =401a(8) =2609a(9) =19802a(10) =171437a(11) =1664585a(12) =17892938a(13) =210771761a(14) =2698597601a(15) =37301188610a(16) =553473138677
External references
- oeis: A259870