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Putnam
1958 November Putnam
A5
A5
Part of
1958 November Putnam
Problems
(1)
Putnam 1958 November A5
Source: Putnam 1958 November
7/19/2022
Show that the number of non-zero integers in the expansion of the
n
n
n
-th order determinant having zeroes in the main diagonal and ones elsewhere is
n
!
(
1
−
1
1
!
+
1
2
!
−
1
3
!
+
⋯
+
(
−
1
)
n
n
!
)
.
n ! \left(1- \frac{1}{1!} + \frac{1}{2!} - \frac{1}{3!} + \cdots + \frac{(-1)^{n}}{n!} \right) .
n
!
(
1
−
1
!
1
+
2
!
1
−
3
!
1
+
⋯
+
n
!
(
−
1
)
n
)
.
Putnam
matrix
combinatorics