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The Challenge:
Consider the function F(N) = 2^N + 1 where N is a positive integer less than 31. The sequence defined by this function is:
3, 5, 9, 17, 33, 65, 129, 257, 513, 1025, 2049, 4097, 8193, 16385, 32769, 65537, 131073, 262145, 524289, 1048577, 2097153, 4194305, 8388609, 16777217, 335544...