pigeonhole box
The finite category every object in a pigeonhole argument is sorted into, rarely handed over explicitly by the problem.
In a pigeonhole argument, the boxes are a finite, fixed set of categories every object must fall into; the argument forces a collision once the object count exceeds the box count.
Examples
For a shared-remainder argument mod m, the boxes are the m possible remainders, not the objects themselves.
See also
Point table
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