IBM Ponder This #178 · February 2013

James Tanton tweeted ( https://twitter.com/jamestanton/status/293127359291330561) that "16 and 9 are each square numbers, and putting them together, 169, gives another square" and he then asked for other examples.

Our challenge this month is to find integers x, y, and z such that concatenating x^2 and y^2 gives z^2, and that z has at least four consecutive nines.

Update 2/6: the challenge stating that x,y and z should be non-zero.

Solution

Best opened after a real attempt

To be added.