283243

Appears in sequences

• Number of vertices in a polygon whose boundary consists of n+2 equally spaced points around a semicircle and n+2 equally spaced points along the diameter (a total of 2n+2 points). See Comments for precise definition.at n=28A334458
• Triangle of number of interval-closed sets T(m,n) in the product of two chains [m]x[n], for m <= n, read by rows.at n=32A367109