Number of permutations p of 1,2,...,n satisfying p(i+6)-p(i)<>6 for all 1<=i<=n-6.
A189285
Number of permutations p of 1,2,...,n satisfying p(i+6)-p(i)<>6 for all 1<=i<=n-6.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =24a(5) =120a(6) =720a(7) =4920a(8) =37488a(9) =319644a(10) =3033264a(11) =31784280a(12) =364902480a(13) =4538652840a(14) =61102571376a(15) =885045657564
External references
- oeis: A189285