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2016 Online Math Open Problems
1
2015-2016 Spring OMO #1
2015-2016 Spring OMO #1
Source:
March 29, 2016
Online Math Open
Problem Statement
Let
A
n
A_n
A
n
denote the answer to the
n
n
n
th problem on this contest (
n
=
1
,
…
,
30
n=1,\dots,30
n
=
1
,
…
,
30
); in particular, the answer to this problem is
A
1
A_1
A
1
. Compute
2
A
1
(
A
1
+
A
2
+
⋯
+
A
30
)
2A_1(A_1+A_2+\dots+A_{30})
2
A
1
(
A
1
+
A
2
+
⋯
+
A
30
)
.Proposed by Yang Liu
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