Difference between revisions of "2004 AIME II Problems/Problem 8"
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Revision as of 22:21, 4 July 2013
Problem
How many positive integer divisors of
are divisible by exactly 2004 positive integers?
Solution
The prime factorization of 2004 is
. Thus the prime factorization of
is
.
We can count the number of divisors of a number by multiplying together one more than each of the exponents of the prime factors in its prime factorization. For example, the number of divisors of
is
.
A positive integer divisor of
will be of the form
. Thus we need to find how many
satisfy
We can think of this as partitioning the exponents to
and
. So let's partition the 2's first. There are two 2's so this is equivalent to partitioning two items in three containers. We can do this in
ways. We can partition the 3 in three ways and likewise we can partition the 167 in three ways. So we have
as our answer.
See also
| 2004 AIME II (Problems • Answer Key • Resources) | ||
| Preceded by Problem 7 |
Followed by Problem 9 | |
| 1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 | ||
| All AIME Problems and Solutions | ||
These problems are copyrighted © by the Mathematical Association of America, as part of the American Mathematics Competitions.