An algorithm is a sequence of steps to be followed to accomplish a certain task. Often used in computer programming, they can become interesting puzzles because even though there can be many ways to accomplish something, one may be better than another.
How many distinct distributions (x,y,z,w) of n
identical marbles in 4 boxes labeled A,B,C and D are there, such that
x,y,z,w are positive integers in strictly increasing order?
Verify the validity of your formula (or set of formulas) by manual listing of all such distributions for n=18.
Latest: 
