a(n) = (n-1)*a(n-1) - n*a(n-2), with a(1) = a(2) = -1.
A356684
a(n) = (n-1)*a(n-1) - n*a(n-2), with a(1) = a(2) = -1.
Terms
- a(0) =-1a(1) =-1a(2) =1a(3) =7a(4) =23a(5) =73a(6) =277a(7) =1355a(8) =8347a(9) =61573a(10) =523913a(11) =5024167a(12) =53479135a(13) =624890417a(14) =7946278813a(15) =109195935523
External references
- oeis: A356684