5.4 The Cofactors of the Matsuno Determinant 193
(
E
ii
+
∂
∂xi
)
E
pru,qsv
=e
ipru,iqsv
, (5.4.4)
etc.
5.4.2 First Cofactors.....................
Whenfr+gr= 0, the double-sum identities (C) and (D) in Section 3.4
become
n
∑
r=1
n
∑
s=1
†
(fr+gs)arsA
rs
=0, (C
†
)
n
∑
r=1
n
∑
s=1
†
(fr+gs)arsA
is
A
rj
=(fi+gj)A
ij
. (D
†
)
Applying (C
†
)toEwithfr=−gr=c
m
r
,
n
∑
r=1
n
∑
s=1
†
(
c
m
r
−c
m
s
cr−cs
)
E
rs
=0. (5.4.5)
Puttingm=1, 2 ,3 yields the following particular cases:
m=1:
∑
r
∑
s
†
E
rs
=0,
which is equivalent to
∑
r
∑
s
E
rs
=
∑
r
E
rr
; (5.4.6)
m=2:
∑
r
∑
s
†
(cr+cs)E
rs
=0,
which is equivalent to
∑
r
∑
s
(cr+cs)E
rs
=2
∑
r
crE
rr
; (5.4.7)
m=3:
∑
r
∑
s
†
(c
2
r+crcs+c
2
s)E
rs
=0,
which is equivalent to
∑
r
∑
s
(c
2
r
+crcs+c
2
s
)E
rs
=3
∑
r
c
2
r
E
rr
. (5.4.8)
Applying (D
†
)toE, again withfr=−gr=c
m
r,
∑
r
∑
s
†
(
c
m
r −c
m
s
cr−cs
)
E
is
E
rj
=(c
m
i
−c
m
j
)E
ij
. (5.4.9)
Puttingm=1,2 yields the following particular cases: