i'll be glad to read your explanation of using binomial coefficients..

was my first intuition but my math fu is so low. Thanks anyway for the clever solution.

L*
There are no rules, there are no thumbs..
Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.

In reply to Re^2: Combinatorics problem. by Discipulus
in thread Combinatorics problem. (Updated with more info.) by BrowserUk

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