|  | 1. | This equivalence relation is a semigroup congruence, as defined above. 
 
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|  | 2. | The affine concept of parallelism forms an equivalence relation on lines. 
 
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|  | 3. | Binary relations that are both reflexive and Euclidean are equivalence relations. 
 
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|  | 4. | This defines an equivalence relation on the set of almost homomorphisms. 
 
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|  | 5. | Since x \ sim _ j y is an equivalence relation. 
 
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|  | 6. | For example, an equivalence relation possesses cycles but is transitive. 
 
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|  | 7. | Any homomorphism defines an equivalence relation on by if and only if. 
 
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|  | 8. | Like any equivalence relation, a semigroup congruence \ sim induces congruence classes 
 
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|  | 9. | In the next step, one imposes a set of equivalence relations. 
 
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|  | 10. | This equivalence relation is an abstraction of the germ equivalence described above. 
 
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