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17
D 17
D 17
Source:
May 25, 2007
modular arithmetic
Congruences
Problem Statement
Determine all positive integers
n
n
n
such that
x
y
+
1
≡
0
(
m
o
d
n
)
xy+1 \equiv 0 \; \pmod{n}
x
y
+
1
≡
0
(
mod
n
)
implies that
x
+
y
≡
0
(
m
o
d
n
)
x+y \equiv 0 \; \pmod{n}
x
+
y
≡
0
(
mod
n
)
.
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