KöMaL 2013 B4575
According to the tradition of the ancient tribe of Head Counters, every year is designated either as lucky or as sinister. For example, 2013 is a lucky year since the first 2013 positive integers can be partitioned into at least two classes such that each class contains the same number of elements and the sum of the elements is also equal in each class. If such a partition does not exist, the year is said to be sinister. Which years are sinister?
Official text KöMaL. Quoted with source.
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