228 5. Further Determinant Theory
identities in whichr=±1 form a dual pair in the sense that one can be
transformed into the other by interchangingHsandhs,s=0, 1 , 2 ,....
Examples.
(n, r)=(2,0):
∣
∣
∣
∣
H 2 H 3
H 1 H 2
∣
∣
∣
∣
=
∣
∣
∣
∣
h 2 h 3
h 1 h 2
∣
∣
∣
∣
;
(n, r)=(3,0):
∣ ∣ ∣ ∣ ∣ ∣
H 3 H 4 H 5
H 2 H 3 H 4
H 1 H 2 H 3
∣ ∣ ∣ ∣ ∣ ∣
=
∣ ∣ ∣ ∣ ∣ ∣
h 3 h 4 h 5
h 2 h 3 h 4
h 1 h 2 h 3
∣ ∣ ∣ ∣ ∣ ∣
;
(n, r)=(2,1):
∣
∣
∣
∣
H 3 H 4
H 2 H 3
∣
∣
∣
∣
=
∣ ∣ ∣ ∣ ∣ ∣
h 2 h 3 h 4
h 1 h 2 h 3
1 h 1 h 2
∣ ∣ ∣ ∣ ∣ ∣
;
(n, r)=(3,−1):
∣ ∣ ∣ ∣ ∣ ∣
H 2 H 3 H 4
H 1 H 2 H 3
1 H 1 H 2
∣ ∣ ∣ ∣ ∣ ∣
=
∣
∣
∣
∣
h 3 h 4
h 2 h 3
∣
∣
∣
∣
.
Conjecture 2.
∣
∣
∣
∣
Hn Hn+1
1 H 1
∣
∣
∣
∣
=
∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣
h 2 h 3 h 4 h 5 ··· hn hn+1
1 h 1 h 2 h 3 ··· hn− 2 hn− 1
1 h 1 h 2 ··· hn− 3 hn− 2
1 h 1 ··· hn− 4 hn− 3
··· ··· ··· ···
1 h 1
∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ ∣ n
.
Note that, in the determinant on the right, there is a break in the sequence
of suffixes from the first row to the second.
The following set of identities suggest the existence of a more general
relation involving determinants in which the sequence of suffixes from one
row to the next or from one column to the next is broken.
∣
∣
∣
∣
H 1 H 3
1 H 2
∣
∣
∣
∣
=
∣
∣
∣
∣
h 1 h 3
1 h 2
∣
∣
∣
∣
,
∣
∣
∣
∣
H 2 H 4
H 1 H 3
∣
∣
∣
∣
=
∣
∣
∣
∣
∣
∣
h 1 h 3 h 4
1 h 2 h 3
h 1 h 2
∣
∣
∣
∣
∣
∣
,
∣
∣
∣
∣
H 3 H 5
H 2 H 4
∣
∣
∣
∣
=
∣ ∣ ∣ ∣ ∣ ∣ ∣
h 1 h 3 h 4 h 5
1 h 2 h 3 h 4
h 1 h 2 h 3
1 h 1 h 2