Number of Wilf-equivalence classes of square permutations of 2n things that avoid 123.
A279201
Number of Wilf-equivalence classes of square permutations of 2n things that avoid 123.
Terms
- a(0) =1a(1) =2a(2) =12a(3) =118a(4) =1218a(5) =14272
External references
- oeis: A279201