94974

Appears in sequences

• Least k > 1 such that the product pen(n) * pen(k) is pentagonal, or zero if no such k exists, where pen(k) is the k-th pentagonal number.at n=5A212615
• a(n) = 4*n^3 - 3*n^2 - 2*n - 1.at n=29A268644