347544

Appears in sequences

• Number of permutations of {1,...,n} avoiding adjacent step pattern up, up, down, down, up, up.at n=9A177549
• Place n equally spaced points on each side of a square, and join each of these points by a chord to the 3*n new points on the other three sides: sequence gives number of regions in the resulting planar graph.at n=15A367278