deletions | additions       diff --git a/Show_there_is_a_one__.tex b/Show_there_is_a_one__.tex  index a28b87f..9e66c12 100644  --- a/Show_there_is_a_one__.tex  +++ b/Show_there_is_a_one__.tex 
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Show there is a one-to-one correspondence from the set \mathbb{N} \[\mathbb{N}\]  of natural numbers to the set \mathbb{Z}\times \mathbb{Z} \[\mathbb{Z}\times \mathbb{Z}\]  of ordered pairs of integers. (Draw a picture of part of \mathbb{Z}\times \mathbb{Z} \[\mathbb{Z}\times \mathbb{Z}\]  around (0,0)). \[(0,0))\].