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Sweden Contests
Swedish Mathematical Competition
1986 Swedish Mathematical Competition
3
3
Part of
1986 Swedish Mathematical Competition
Problems
(1)
pairs with q < 2are equally numbered as those with q > 2, if q = b/a
Source: 1986 Swedish Mathematical Competition p3
3/28/2021
Let
N
≥
3
N \ge 3
N
≥
3
be a positive integer. For every pair
(
a
,
b
)
(a,b)
(
a
,
b
)
of integers with
1
≤
a
<
b
≤
N
1 \le a <b \le N
1
≤
a
<
b
≤
N
consider the quotient
q
=
b
/
a
q = b/a
q
=
b
/
a
. Show that the pairs with
q
<
2
q < 2
q
<
2
are equally numbered as those with
q
>
2
q > 2
q
>
2
.
algebra
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