1997 IMO Problems/Problem 6

Problem

For each positive integer $n$, let $f(n)$ denote the number of ways of representing $n$ as a sum of powers of $2$ with nonnegative integer exponents. Representations which differ only in the ordering of their summands are considered to be the same. For instance, $f(4)=4$, because the number 4 can be represented in the following four ways:

$4;2+2;2+1+1;1+1+1+1$

Prove that, for any integer $n \ge 3$,

$2^{n^{2}/4}<f(2^{n})<2^{n^{2}/2}$.

Solution

This problem needs a solution. If you have a solution for it, please help us out by adding it.

See Also

1997 IMO (Problems) • Resources
Preceded by
Problem 5
1 2 3 4 5 6 Followed by
Last Question
All IMO Problems and Solutions