213831

Appears in sequences

• Numbers n such that there are integers a < b with a^2+(a+1)^2+...+(n-1)^2 = (n+1)^2+(n+2)^2+...+b^2.at n=15A094552
• Triangle read by rows: T(n,k) is the number of unsensed combinatorial maps with n edges and k vertices, 1 <= k <= n + 1.at n=37A380616
• Number of unsensed combinatorial maps with n edges and 2 vertices.at n=7A380620