Is the N-Grad students grabbing a beer problem decidable?

[Michael Oltmans <moltmans@>]

Grad student 1: "Hey let's go out and get a drink."
Grad student 2: "Ok, where should we go."
Grad student 1: "Hang on, let's see if grad student 3 is around."

...1 and 2 go find 3...

Grad student 3: "Hey, I was just going to go grab a drink with student 
4, want to come?"
Grad student 2: "Sure, we were just on our way out.  Where are you going."
Grad student 3: "It doesn't matter, we can go where ever you were 
thinking of going to."
Grad student 1: "We don't know."
Grad student 3: "Hey, there's grad student 4... Grad student 4, you want 
to grab a drink."
Grad student 4: "Ummm.... yeah, but the thing is I have this project, 
and my adviser..."
Grad student 2: "Don't be lame, just come."
Grad student 4: "Well, maybe I can come back afterward and finish up. 
Where are you going?"
Grad student 3: "Well...Let's ask Grad student 5, she knows cool places 
to go."

Is the N-Grad students grabbing a beer problem decidable?  If so is the 
choosing a location for N-Grad students grabbing a beer at a specific 
location decidable?

We've got the goods and we've got the location so come increase N at 
tonights extra special "lets avoid using the pumping lemma" theory 
edition of...

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             girl scout benefit -+-  5:30 pm  -+- 7ai playroom
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             [ for those coming from elsewhere: building ne43,
               http://whereis.mit.edu/bin/map?locate=bldg_ne43 ]