a(n) = n!*b(n), where b(n) = ((n-1)^2 - 2)*b(n-2)/(n*(n-1)) and b(0) = b(1) = 1.
A123026
a(n) = n!*b(n), where b(n) = ((n-1)^2 - 2)*b(n-2)/(n*(n-1)) and b(0) = b(1) = 1.
Terms
- a(0) =1a(1) =1a(2) =-1a(3) =2a(4) =-7a(5) =28a(6) =-161a(7) =952a(8) =-7567a(9) =59024a(10) =-597793a(11) =5784352a(12) =-71137367a(13) =821377984a(14) =-11879940289a(15) =159347328896
External references
- oeis: A123026