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SEEMOUS
2012 SEEMOUS
Problem 1
Problem 1
Part of
2012 SEEMOUS
Problems
(1)
A=a_ij=i^j+j^i mod 3, det A≠0
Source: SEEMOUS 2012 P1
6/9/2021
Let
A
=
(
a
i
j
)
A=(a_{ij})
A
=
(
a
ij
)
be the
n
×
n
n\times n
n
×
n
matrix, where
a
i
j
a_{ij}
a
ij
is the remainder of the division of
i
j
+
j
i
i^j+j^i
i
j
+
j
i
by
3
3
3
for
i
,
j
=
1
,
2
,
…
,
n
i,j=1,2,\ldots,n
i
,
j
=
1
,
2
,
…
,
n
. Find the greatest
n
n
n
for which
det
A
≠
0
\det A\ne0
det
A
=
0
.
matrix
linear algebra
number theory