How many 6-permutations of [15] have their digits listed in increasing order? (where [15] is the set of positive intergers <= 15)

I am thinking that this would be just .

Consider 3-permutations of [5] in increasing order...

123 124 125 134 135 145 234 235 245 345 which has 10 different members which is .

Would this be correct?