A374271 a(n) is the smallest number which can be represented as the sum of n distinct n-th powers of primes in exactly 3 ways, or -1 if no such number exists.
-1, 2210, 8627527, 616151524, 876639080351
Offset: 1
Examples
a(2) = 2210 = 19^2 + 43^2 = 23^2 + 41^2 = 29^2 + 37^2. a(3) = 8627527 = 19^3 + 151^3 + 173^3 = 23^3 + 139^3 + 181^3 = 71^3 + 73^3 + 199^3.