...For example, when a single number like 6 is displayed, you can press 6 directly or a sequence of numbers that add up to 6 like 1, 2 and 3 or 2 and 4 or 1 and 5. Also, if a number like 11 is shown as the target number, you can press 2 and 9 or 3 and 8 or 4 and 7 or 1, 3 and 7 or 2, 3 and 6 or 5 and 6. For any target number the goal is to add up to it.
A high number like 30 requires a sequence that can vary like 1, 9, 2, 8, 4 and 6. The goal still being that the sum of the sequence adds up to 30. Because there is a limit to how many numbers can be summed, the limit of the target numbers is 40.
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