How many of the numbers from the set \(\{1,\ 2,\ 3,\ldots,\ 50\}\) have a perfect square factor other than one?
I think you mean
4 9 16 25 36 49 Six
I count 18 which have at least 1 perfect square as a factor or divisor:
(4, 8, 9, 12, 16, 18, 20, 24, 25, 27, 28, 32, 36, 40, 44, 45, 48, 50)
Don't forget 49
Right. Thanks.
+885 
