Number of permutations of 1..n with i-8<=p(i)<=i+7.

Terms

a(0) =1a(1) =2a(2) =6a(3) =24a(4) =120a(5) =720a(6) =5040a(7) =40320a(8) =322560a(9) =2333520a(10) =15613200a(11) =99001320a(12) =608500536a(13) =3693175530a(14) =22447207906a(15) =138027417451a(16) =864806272861