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2018-IMOC
N6
N6
Part of
2018-IMOC
Problems
(1)
Z->Z polynomial, summation with +-1 coefficients
Source: IMOC 2018 N6
8/18/2021
If
f
f
f
is a polynomial sends
Z
\mathbb Z
Z
to
Z
\mathbb Z
Z
and for
n
∈
N
≥
2
n\in\mathbb N_{\ge2}
n
∈
N
≥
2
, there exists
x
∈
Z
x\in\mathbb Z
x
∈
Z
so that
n
∤
f
(
x
)
n\nmid f(x)
n
∤
f
(
x
)
, show that for every
k
∈
Z
k\in\mathbb Z
k
∈
Z
, there is a non-negative integer
t
t
t
and
a
1
,
…
,
a
t
∈
{
−
1
,
1
}
a_1,\ldots,a_t\in\{-1,1\}
a
1
,
…
,
a
t
∈
{
−
1
,
1
}
such that
a
1
f
(
1
)
+
…
+
a
t
f
(
t
)
=
k
.
a_1f(1)+\ldots+a_tf(t)=k.
a
1
f
(
1
)
+
…
+
a
t
f
(
t
)
=
k
.
algebra
polynomial
number theory