56065

Appears in sequences

• Number of intersections inside an equilateral triangular figure formed by the straight line segments mutually connecting all vertices and all points that divide the sides into n equal parts. If three or more lines meet at an interior point this intersection is counted only once.at n=13A092866
• a(n) = 1681*n^2 - 756*n + 85.at n=5A157010
• Numbers k such that 4^k + 25 is prime.at n=33A204388
• T(n,k) is the number of non-equivalent distinguishing coloring partitions of the cycle on n vertices with exactly k parts. Regular triangle read by rows, n >= 1, 1 <= k <= n.at n=71A309784