49570

Appears in sequences

• Numbers k such that sigma(sigma(k) - k) = phi(sigma(k) + k).at n=24A074886
• Number of nondecreasing -2..2 vectors of length n whose dot product with some nonincreasing -2..2 vector equals n.at n=37A226393
• a(n) is the smallest positive integer which can be represented as the sum of n distinct nonzero square pyramidal numbers in exactly n ways, or -1 if no such integer exists.at n=23A360218