To find the greatest positive integer x such that 236+x divides 2000!, we need to determine how many times the prime factor 23 appears in the prime factorization of 2000!.
The exponent of a prime p in n! is given by:
k=1∑∞⌊pkn⌋
In this case, n=2000 and p=23.
Let's calculate each term until we reach a power where the division results in a number less than 1:
1. ⌊232000⌋=⌊86.95652⌋=86
2. ⌊2322000⌋=⌊5292000⌋=⌊3.78337⌋=3
3. ⌊2332000⌋=⌊121672000⌋=⌊0.16438⌋=0
For higher powers of 23, such as 234, the floor function results in 0, since 234=279841 is greater than 2000.
Therefore, the total number of times 23 appears as a factor in 2000! is:
86+3+0=89
We want 236+x to divide 2000!, so we set:
6+x≤89
Solving for x, we get:
x≤83
Therefore, the greatest positive integer x is:
83