Someone said,

> 
> ***"Where is Nash?"***
> 
> 
> 

And the other answerd,

> 
> ***"He hasn't shown."***
> 
> 
> 

My question is, I wonder if it works even without "up", 

Shouldn't it have written like this? : He hasn't shown **up**.

Isn't "Up" necessary, is it?