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CIIM
2010 CIIM
Problem 5
CIIM 2010 Problem 5
CIIM 2010 Problem 5
Source:
June 9, 2016
CIIM
CIIM 2010
undergraduate
Problem Statement
Let
n
,
d
n,d
n
,
d
be integers with
n
,
k
>
1
n,k > 1
n
,
k
>
1
such that
g
.
c
.
d
(
n
,
d
!
)
=
1
g.c.d(n,d!) = 1
g
.
c
.
d
(
n
,
d
!)
=
1
. Prove that
n
n
n
and
n
+
d
n+d
n
+
d
are primes if and only if
d
!
d
(
(
n
−
1
)
!
+
1
)
+
n
(
d
!
−
1
)
≡
0
(
m
o
d
n
(
n
+
d
)
)
.
d!d((n-1)!+1) + n(d!-1) \equiv 0 \hspace{0.2cm} (\bmod n(n+d)).
d
!
d
((
n
−
1
)!
+
1
)
+
n
(
d
!
−
1
)
≡
0
(
mod
n
(
n
+
d
))
.
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