write the following expression as a single combination, so that k does not equal 1 and n-k does not equal 1.
(10 choose 4) + (10 choose 5) + (11 choose 5) + (12 choose 5) + ..... + (29 choose 5) + (30 choose 5)= n choose k
(10 choose 4) + (10 choose 5) + (11 choose 5) + (12 choose 5) + ..... + (29 choose 5) + (30 choose 5)= 736,281
736,281 ==31 choose 25, or:
736,281 ==31 choose 6
