How to work?
To see how the pattern develops click
GO down below all the instructions.
Read the instructions on each page carefully.
Then click START.
Type the answer for the given addition in
the empty box. If required, change the answer
by deleting the earlier answer.
Then click OK.
Read the message you get.
When finished follow the other instructions
Remember, if you click Cancel you will lose
the chance of checking correctness of your
When you click 'Show Table ...', a new
window will open for you. It can be closed by
just clicking the 'x', in its top-right-corner.
So enjoy here!