Number of permutations of length n which avoid the patterns 4123 and 3412.
A165544
Number of permutations of length n which avoid the patterns 4123 and 3412.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =22a(5) =89a(6) =381a(7) =1696a(8) =7781a(9) =36572a(10) =175277a(11) =853410a(12) =4209376a(13) =20988122a(14) =105611537a(15) =535638107
External references
- oeis: A165544