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relations/digraphs (really basic)

why is there an arrow pointing from 2 to 1 if s must be less than t? the arrow from 1 to 2 makes sense because 1 < 2

why is there an arrow pointing from 2 to 3? or from 1 to 3?

if anyone can explain this to me i'll be really grateful

cheers
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sputum
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I can't really help much more than saying 1, 2 and 3 are representing members (or sets of members) of S3 rather than numbers.
Is there any more context you could give?
(edited 12 years ago)
Original post by tourettes guy
why is there an arrow pointing from 2 to 1 if s must be less than t? the arrow from 1 to 2 makes sense because 1 < 2

why is there an arrow pointing from 2 to 3? or from 1 to 3?

if anyone can explain this to me i'll be really grateful

cheers


The criteria is "s < t" OR "s%2 < t%2" where % is the remainder on division of the first number by the second.

So, 1<2, 1<3, 2<3 accounts for 3 of the arrows.

And the arrow from 2 to 1 is because 2%2 (=0) is less than 1%2 (=1)

For ref for anyone else see:
http://www.scribd.com/doc/63879076/29/Graphical-representation-of-relations sections 3.3 to 3.5
(edited 12 years ago)

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