Sum of how many squares of successive positive integers is a square number?

Surprisingly enough, trivial answer discounted, only one number qualifies!

(In reply to Cannonball! by Brian Smith)

a.  You are right.  My original intention was re sequence beginning with 1 and the proper beginning should have been   "Consider the series   1^2+2^2+... n^2.      "  My bad.

b. Your formula lacks  /6    on the right side of the equation. Please edit.

c. Never heard of  "Cannonball" problem, will look it up. Tnx.

Posted by Ady TZIDON on 2017-04-04 00:17:29