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1992 IMO Longlists
62
Exist k_i for such c_i - IMO LongList 1992 ROM1
Exist k_i for such c_i - IMO LongList 1992 ROM1
Source:
September 2, 2010
inequalities
algebra
Sequence
IMO Shortlist
IMO Longlist
Problem Statement
Let
c
1
,
⋯
,
c
n
(
n
≥
2
)
c_1, \cdots, c_n \ (n \geq 2)
c
1
,
⋯
,
c
n
(
n
≥
2
)
be real numbers such that
0
≤
∑
c
i
≤
n
0 \leq \sum c_i \leq n
0
≤
∑
c
i
≤
n
. Prove that there exist integers
k
1
,
⋯
,
k
n
k_1, \cdots , k_n
k
1
,
⋯
,
k
n
such that
∑
k
i
=
0
\sum k_i=0
∑
k
i
=
0
and
1
−
n
≤
c
i
+
n
k
i
≤
n
1-n \leq c_i + nk_i \leq n
1
−
n
≤
c
i
+
n
k
i
≤
n
for every
i
=
1
,
⋯
,
n
.
i = 1, \cdots , n.
i
=
1
,
⋯
,
n
.
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