a(n) = n * a(n-1) - Sum_{k=1..n-2} a(k) with a(1) = 0 and a(2) = 1.
A056199
a(n) = n * a(n-1) - Sum_{k=1..n-2} a(k) with a(1) = 0 and a(2) = 1.
Terms
- a(0) =0a(1) =1a(2) =3a(3) =11a(4) =51a(5) =291a(6) =1971a(7) =15411a(8) =136371a(9) =1345971a(10) =14651571a(11) =174318771a(12) =2249992371a(13) =31309422771a(14) =467200878771
External references
- oeis: A056199