Number of standard permutations of [ a_1..a_n b_1..b_n ] (b_i is not immediately followed by a_i, for all i).
A033815
Number of standard permutations of [ a_1..a_n b_1..b_n ] (b_i is not immediately followed by a_i, for all i).
Terms
- a(0) =1a(1) =1a(2) =14a(3) =426a(4) =24024a(5) =2170680a(6) =287250480a(7) =52370755920
External references
- oeis: A033815