Number of permutations of [n] avoiding the pattern 1-23-4.
A113227
Number of permutations of [n] avoiding the pattern 1-23-4.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =23a(5) =105a(6) =549a(7) =3207a(8) =20577a(9) =143239a(10) =1071704a(11) =8555388a(12) =72442465a(13) =647479819a(14) =6083742438a(15) =59885558106a(16) =615718710929
External references
- oeis: A113227