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Russian TST 2019
P2
Congruence modulo p^2
Congruence modulo p^2
Source: Russian TST 2019, Day 6 P2
March 22, 2023
number theory
congruence
Problem Statement
Prove that for every odd prime number
p
p{}
p
, the following congruence holds
∑
n
=
1
p
−
1
n
p
−
1
≡
(
p
−
1
)
!
+
p
(
m
o
d
p
2
)
.
\sum_{n=1}^{p-1}n^{p-1}\equiv (p-1)!+p\pmod{p^2}.
n
=
1
∑
p
−
1
n
p
−
1
≡
(
p
−
1
)!
+
p
(
mod
p
2
)
.
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