MathDB
Problems
Contests
National and Regional Contests
Iran Contests
Pre-Preparation Course Examination
2007 Pre-Preparation Course Examination
22
exist a1,a2,...,an for n-1-Iran 3rd round-Number Theory 2007
exist a1,a2,...,an for n-1-Iran 3rd round-Number Theory 2007
Source:
July 28, 2010
modular arithmetic
number theory
Problem Statement
Prove that for any positive integer
n
≥
3
n \geq 3
n
≥
3
there exist positive integers
a
1
,
a
2
,
⋯
,
a
n
a_1,a_2,\cdots , a_n
a
1
,
a
2
,
⋯
,
a
n
such that
a
1
a
2
⋯
a
n
≡
a
i
(
m
o
d
a
i
2
)
∀
i
∈
{
1
,
2
,
⋯
,
n
}
a_1a_2\cdots a_n \equiv a_i \pmod {a_i^2} \qquad \forall i \in \{1,2,\cdots ,n\}
a
1
a
2
⋯
a
n
≡
a
i
(
mod
a
i
2
)
∀
i
∈
{
1
,
2
,
⋯
,
n
}
Back to Problems
View on AoPS