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Puzzles/Easy Sequence 8/Solution
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This series is represented by the months. If the month has 31 days, it gets a one. If not, it gets a zero.
Month January February March April May June July August September October November December Length 31 28 or 29 31 30 31 30 31 31 30 31 30 31 Sequence 1 0 1 0 1 0 1 1 0 1 0 1
Alternatively, it can be described as the remainder after dividing by 2 of the length of each month in a common year (as opposed to a leap year).