46570

Appears in sequences

• Table read by antidiagonals: Place k equally spaced points on each side of a regular n-gon and join every pair of these n*k points by a chord; T(n,k) (n >= 3, k >= 0) gives the number of internal vertices in the resulting planar graph.at n=47A367303
• a(n) = (2*n^3 - 6*n^2 + 19*n - 9)*n/6.at n=19A378023