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What is the largest integer n such that 3^n is a factor of 1 x 3 x 5 x... x 97 x 99?

How many of those numbers has a factor of 3

3,6,9, ........99     There are 33 of them

Divide each of these by 3

1,2,3,......  33

Which of these have a factor of 3

3,6,9, ... 33       There are 11 of them

Divide each of these by 3

1,2,3,......  11

Which of these have a factor of 3

3,6,9      There are 3 of them

Divide each of these by 3

1,2,3

Which of these have a factor of 3

3      There are 1 of them

33+11+3+1= 48

I think that the largest n is 48

See https://web2.0calc.com/questions/help_40754#r2

We have yet another annoying situation where someone posts the question twice instead of continuing the original post!

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