UNIX for Dummies Questions & Answers

Hi,
I'm new here so please excuse any stupidity that occurs in my post :P
My situation:
Have a java program which I have to run a ridiculous amount of times and put the output data into a text file.
Thought the easiest way to do this would be to delve into the world of scripts.
I am at home (on a mac) with remote access to my university computers (linux).
Wrote a script which I think might possibly work:

Code:

i=50
while [ $i <= 1000]
do
    java RMIClient telford-00 1090 $i > "$i.txt"
    count='expr $i + 10'
done

I uploaded it into the same directory as the code
Followed some instructions on the internet to chmod it using:

Code:

chmod +x RMIScript.sh

Where RMIScript is the name of the script.

Tried to run it using both:

Code:

sh ./RMIScript.sh

and

Code:

./RMIScript.sh

however both come out with errors 'cannot open =: No such file'

Any advice would be appreciated.

Edit:
Changed code to:

Code:

i=50
while [ $i -lt 1000]
do
    java RMIClient telford-00 1090 $i > "$i.txt"
    i=$[i + 10]
done

same error.

come out with errors 'cannot open =: No such file'

Paste the error as it is, this way we will be able to identify the issue.