859536

Appears in sequences

• a(1) = 1, a(2) = 2, a(3) = 2, a(4) = 3, for n >= 3, a(n+2) = a(n+1) + a(n)*floor(n/2)*ceiling(n/2).at n=12A098738
• Triangle read by rows: T(n,k) is the number of polygons formed by connecting the vertices of a regular 2n-gon such that the winding number around the center is k and with no side passing through the center.at n=17A343369