How many chickens do you recommend for a 17x14 run?
The Usual Guidelines aren't hard-and-fast RULES, but the 10 square feet per chicken in the run makes a good starting point.
However, to get a good picture of what 4 square feet in the coop and 10 square feet in the run really means, consider the fact that it's exactly the size of a large bathmat next to that little, 2'x5', fiberglass tub/shower combo drop-in that you find in the hall bathroom of a modest manufactured home.

The square footage of that run suggests about 23 chickens -- but that may or may not work depending on the individual chickens and your management methods.