Thanks Alan
Ok, WolframAlpha and Alan both agree that the answer is 26 so where did I go wrong...
I did not account for the even numbers to be missing.
I found the power if all the numbers from 1 to 99 were multiplied together.
Silly me,
I will try my way again,
3,9,15,21,27,33,39,45,51,57,63,69,75,81,87, 93,99 are all divisible by 3 (That is 17 numbers)
divide by 3
1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33
which of these are divisible by 3
3,9,15,21,27,33 (That is 6 numbers)
Divide by 3
1,3,5,7,9,11
which of these are divisible by 3
3,9, (That is 2 numbers)
Divide by 3
1,3
which of these are divisible by 3
3, (That is 1 number)
17+6+2+1 = 26
Now we are in agreement