I decided to try my hand at making a puzzle game based on elementary math:

Free: https://play.google.com/store/apps/details?id=kulmainen.matharrayfree

Paid: https://play.google.com/store/apps/details?id=kulmainen.matharray

At the simplest level, you are given a number (say, 4) and you have to find two adjacent numbers in an array (say, 3 and 1) such that their sum is the given number. They will then disappear and you have to clear the whole array like this. But of course the game gets more complicated, and you can skip the easiest levels if you want.

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