46 NOTE ON THE THEORY
OF DETERMINANTS. [309
expressions J123...m|, which are obtained
all but one of the m symbols.
This being so, and writing for greater simplicity | 1 | 2 | to denote the product
|1 | x | 21, and so in general, the values of the determinants {12}, {123}, {1234}, {12345},
&c. are as follows: viz.
by permuting in every possible manner
No. of terms.
+
{12} = + | 1 | 2 | ....
1
-|1 2| ....
1
1+ 1 =
{123} = + | 1 | 2 | 3 | ...
1
~ 1 1 2 | 3 | ...
3
+ | 1 2 3 | ...
2
3+ 3 =
{1234} = + I 1 | 2 | 3 | 4 | . .
1
-|1 2| 3|4 | . .
6
+ | 1 2 3 | 4 | . .
8
+ | 1 2 | 3 4 | . .
3
- | 1 2 3 4 | . .
6
12+12 =
{12345} = + | 1 | 2 | 3 | 4 | 5 | .
1
-|1 2 1 3 | 4 [ 5 | .
10
+ | 1 2 3 | 4 | 5 | .
20
+ | 1 2 | 3 4 | 5 | .
15
- | 1 2 3 4 | 5 | .
30
- | 1 2 3 | 4 5 | .
20
+ | 1 2 3 4 5 | .
24
60 + 60 =
where, as regards the signs, it is to be observed that there is a sign — for each
compartment | | containing an even number of symbols; thus in the expression for
{1234}, the terms | 1 2 | 3 4 | have the sign = +, and the terms | 1 2 3 4 | the
sign —. Or, what comes to the same thing; when n is even, the sign is + or —
according as the number of compartments is even or odd; and contrariwise when n is
odd. As regards the remaining part of the expression, this merely exhibits the partitions