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PEN E Problems
20
20
Part of
PEN E Problems
Problems
(1)
E 20
Source:
5/25/2007
Verify that, for each
r
≥
1
r \ge 1
r
≥
1
, there are infinitely many primes
p
p
p
with
p
≡
1
(
m
o
d
2
r
)
p \equiv 1 \; \pmod{2^r}
p
≡
1
(
mod
2
r
)
.
modular arithmetic
number theory