630784

Appears in sequences

• Numbers n such that sum of the squares of the prime factors of n equals the sum of the squares of the digits of n.at n=21A067184
• a(n) = n*(n-3)*2^(n-2).at n=14A178987
• Define the array k(n,x) = number of m such that tau(gcd(n,m)) is x where m runs from 1 to n. Also define h(n,x) = Sum_{d|n : tau(d) = x} d. The sequence contains numbers n such that k(n,x)*x = h(n,x) has at least one solution x.at n=30A197099
• Numbers k with canonical prime factorization k = p1^e1*p2^e2*p3^e3 such that the points (p1, e1), (p2, e2) and (p3, e3) form a nondegenerate integer-sided triangle.at n=1A387586