Question 339055
You need to choose 1 suit from the 4 suits: C(4,1)

and 5 cards from the same suit: C(13,5)

C(13,5)*C(4,1)=5148

This includes straight flushes as well.

There are 40 straight flushes (including the 4 royal flushes), so if you want to exclude those the answer is 5108.