Number of permutations of n avoiding the pattern 1231'.
A177483
Number of permutations of n avoiding the pattern 1231'.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =20a(5) =85a(6) =420a(7) =2443a(8) =16136a(9) =120222a(10) =993770a(11) =9042451a(12) =89725944a(13) =964693717a(14) =11168801294a(15) =138549935190
External references
- oeis: A177483