51194

Appears in sequences

• a(n) = Sum_{0<=j<=i, 0<=i<=n} A027907(i, j).at n=10A027915
• The number of edges formed when every pair of n points, placed at the vertices of a regular n-gon, are connected by a circle and where the points lie at the ends of the circle's diameter.at n=20A358783
• Let G_n denote the planar graph defined in A358746 with the addition, if n is odd, of the circle containing the initial n points; sequence gives the number of edges in G_n.at n=21A370977