2908069

Appears in sequences

• Number of staircase polygons of perimeter 2n with 2 (staircase polygon) holes on square lattice (not allowing rotations).at n=6A057411
• The number of length 2n - 1 strings over the alphabet {0, 1} such that the first half of any initial odd length substring is a permutation of the second half.at n=31A297789