Odious number
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In mathematics
In number theory, an odious number is a non-negative number that has an odd number of 1s in its binary expansion.
The first odious numbers are: 1, 2, 4, 7, 8, 11, 13, 14, 16, 19, 21, 22, 25, 26, 28, 31, 32, 35, 37, 38 ... [1]
Numbers that are not odious are called evil numbers.