- #1

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On page 113 Munkres (Topology: Second Edition) defines a J-tuple as follows:

I was somewhat perplexed when I tried to completely understand the function [itex] \ x \ : \ J \to X [/itex].

I tried to write down some specific and concrete examples but still could not see exactly how the function would work.

For example if [itex] J = \{1, 2, 3 \} [/itex] and X was just the collection of all the letters of the alphabet i.e.

[itex] X = \{ a, b, c, ... \ ... \ z \} [/itex] then ...

... obviously a map like 1 --> a, 2 --> d, 3 --> h does not work as the intention, I would imagine is to have a mapping which specifies a number of triples ... but how would this work?

Can someone either correct my example or give a specific concrete example that works.

Would appreciate some help.

Peter

I was somewhat perplexed when I tried to completely understand the function [itex] \ x \ : \ J \to X [/itex].

I tried to write down some specific and concrete examples but still could not see exactly how the function would work.

For example if [itex] J = \{1, 2, 3 \} [/itex] and X was just the collection of all the letters of the alphabet i.e.

[itex] X = \{ a, b, c, ... \ ... \ z \} [/itex] then ...

... obviously a map like 1 --> a, 2 --> d, 3 --> h does not work as the intention, I would imagine is to have a mapping which specifies a number of triples ... but how would this work?

Can someone either correct my example or give a specific concrete example that works.

Would appreciate some help.

Peter