Number of permutations s of {1,2,...,n} such that |s(i)-i|>2 for each i=1,2,...,n.
A075851
Number of permutations s of {1,2,...,n} such that |s(i)-i|>2 for each i=1,2,...,n.
Terms
- a(0) =1a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =1a(7) =8a(8) =112a(9) =1168a(10) =13365a(11) =159414a(12) =2036488a(13) =27780408a(14) =404351752a(15) =6263006598a(16) =102946702825
External references
- oeis: A075851