Friday, August 18, 2006

Divsion problem[S]

Problem : find the maximum value of 'n' such that 18^n divides 181!
See comment for clue[S]

2 comments:

talegari (ತಾಳೆಗರಿ) said...

You may be aware of the problem of type " how many zeroes does 50! end with ?". This means finding maximum 'n' such that 10^n divides 50! or 5^n divides 50! as factors of 2 are found in abundance. Now there is 5 in 5, in 10,... bit 2 fives in 25 and so on.
Using the floor function
[50/5]+[50/5^2]=10+2=12
50! ends with 12 zeroes.

talegari (ತಾಳೆಗರಿ) said...

18=3.3.2
[181/3]=60;[181/9]=20;[181/27]=6;[181/81]=2;
sum/2=44
[181/2]=90 >44
Hence, max power of 18 that divides 181! is 44.