Common Residue
The value of b, where a=b (mod m), taken to be nonnegative and smaller than m.
See also
Minimal Residue, ResidueExplore with Wolfram|Alpha
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Cite this as:
Weisstein, Eric W. "Common Residue." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/CommonResidue.html