Iizuka Congruence

The Iizuka congruence of a Two-Sided Semiring Ideal I R 𝐼 𝑅 I\subseteq R is the Semiring Congruence [ ] I subscript delimited-[] 𝐼 [\approx]_{I} defined as

x[]Iy:=r:R.a,bI.x+a+r=y+b+r\par x[\approx]_{I}y:=\exists r:R.\;\exists a,b\in I.\;x+a+r=y+b+r

This congruence is a coarser version of the Bourne Congruence that adjusts for the fact that addition in a semiring is in general not Cancellative, and can be thought of a sort of "affine" congruence associated to an ideal.

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