deletions | additions       diff --git a/Show_there_is_a_one__.tex b/Show_there_is_a_one__.tex  index 9e66c12..ea2cfd2 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 \[(0,0))\]. $(0,0))$.