List all integers n such that the sum 2^2 + 3^2 + 4^2 + ... + n^2
equals a prime number.
p&p solutions only.
(In reply to solution
Should you have: "the second factor is always > 6"?
Otherwise it could be the one to reduce to 1.
Posted by Jer
on 2017-01-13 16:41:35