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PEN Problems
PEN E Problems
37
37
Part of
PEN E Problems
Problems
(1)
E 37
Source:
5/25/2007
It's known that there is always a prime between
n
n
n
and
2
n
−
7
2n-7
2
n
−
7
for all
n
≥
10
n \ge 10
n
≥
10
. Prove that, with the exception of
1
1
1
,
4
4
4
, and
6
6
6
, every natural number can be written as the sum of distinct primes.
induction
floor function