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Represents a number with 10 symbols, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9
10
(1 * 10^1) + (0 * 10^0) = 10
123
(1 * 10^2) + (2 * 10^1) + (3 * 10^0) = 100 + 20 + 3 = 123
Represents a number with only 2 symbols, 0 or 1
0 1 10 11 100 101 110 111
(1 * 2^2) + (1 * 2^1) + (1 * 2^0) = 4 + 2 + 1 = 7