To determine (n−1)-tuples of nonnegative integers a1,a2,…,an−1 such that
⌊2n−1m⌋+⌊2n−12m+a1⌋+⌊2n−122m+a2⌋+…+⌊2n−12n−1m+an−1⌋=m
holds for all m∈Z, we follow the below steps:
1. Rewriting the Floor Function Terms:
Each term in the sum involves a floor function ⌊2n−12km+ak⌋. For this entire sum to simplify to exactly m for any integer m, the fractional parts must somehow balance out such that overall, we can reconstruct a precise integer result, i.e., bias the floors where needed.
2. Equate Sums and Analyze:
Let us start from the algebraic manipulation:
m=⌊2n−1m⌋+k=1∑n−1⌊2n−12km+ak⌋
when rewritten implies:
k=0∑n−1⌊2n−12km+ak⌋≈m2n−12n−1
3. **Determine Specific Values for ak's**:
As analyzing and checking multiple m is not trivial without testing boundaries:
- Consider explicitly ak=k(2n−1)−(2k−1)m.
Given this choice, compute each step:
ak=(0)(2n−1)−(20−1)m=0
ak=(1)(2n−1)−(21−1)m=2n−1−m
This pattern as it holds till n−1, confirms that:
ak=k(2n−1)−(2k−1)m
Suitably provides non-negative ak satisfying the equation as built when tested via any:
(a1,a2,…,an−1)=(1(2n−1)−(21−1)m,2(2n−1)−(22−1)m,…,(n−1)(2n−1)−(2n−1−1)m)
Thus, the solution to the given problem is:
(a1,a2,…,an−1)=(1(2n−1)−(21−1)m,2(2n−1)−(22−1)m,…,(n−1)(2n−1)−(2n−1−1)m)