English: It as a drawing that shows what a generic surjective application is graphically. It is an application F, from the set X to the set Y .The origin set (X) is marked in blue. The arrival set (Y) is marked in red.
The lower case letter i is a subindex that marks the cardinality of the set Y. The lower case letter j is a subindex that, added to i, marks the cardinality of the set X.
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to remix – to adapt the work
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