Magic in a Square

N² numbers are arranged in a square pattern. Select one of the numbers and try answering computer queries. After two attempts, computer will reveal your selected number. How will it know?

This applet requires Sun's Java VM 2 which your browser may perceive as a popup. Which it is not. If you want to see the applet work, visit Sun's website at https://www.java.com/en/download/index.jsp, download and install Java VM and enjoy the applet.

What if applet does not run?

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