Number of permutations sigma such that |sigma(i+1)-sigma(i)| >= 3 for 1 <= i <= n - 1 and |sigma(i+2)-sigma(i)| >= 3 for 1 <= i <= n - 2.
A279214
Number of permutations sigma such that |sigma(i+1)-sigma(i)| >= 3 for 1 <= i <= n - 1 and |sigma(i+2)-sigma(i)| >= 3 for 1 <= i <= n - 2.
Terms
- a(0) =1a(1) =1a(2) =0a(3) =0a(4) =0a(5) =0a(6) =0a(7) =0a(8) =0a(9) =2a(10) =40a(11) =792a(12) =15374a(13) =281434a(14) =5089060a(15) =93082532a(16) =1743601076a(17) =33694028152
External references
- oeis: A279214