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PEN Problems
PEN O Problems
7
7
Part of
PEN O Problems
Problems
(1)
O 7
Source:
5/25/2007
Show that for each
n
≥
2
n \ge 2
n
≥
2
, there is a set
S
S
S
of
n
n
n
integers such that
(
a
−
b
)
2
(a-b)^2
(
a
−
b
)
2
divides
a
b
ab
ab
for every distinct
a
,
b
∈
S
a, b\in S
a
,
b
∈
S
.
induction
number theory
least common multiple