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1984 IMO Longlists
66
66
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1984 IMO Longlists
Problems
(1)
divisors of n - pigfly #2
Source:
12/27/2004
Let
1
=
d
1
<
d
2
<
.
.
.
.
<
d
k
=
n
1=d_1<d_2<....<d_k=n
1
=
d
1
<
d
2
<
....
<
d
k
=
n
be all different divisors of positive integer n written in ascending order. Determine all n such that:
d
6
2
+
d
7
2
−
1
=
n
d_6^{2} +d_7^{2} - 1=n
d
6
2
+
d
7
2
−
1
=
n
modular arithmetic
number theory unsolved
number theory
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