HP HP-15C - LAST X Register

212 Appendix B: Stack Lift and the LAST X Register
LAST X Register
The following operations save x in the LAST X register:
-
x
H \
k
+
[
H ]
∆
*
\
h
:
÷
]
À
;
a
,
d
p
*
q
{
r
c
*
‘
/
N
z
&
P[
'
w
∕
P\
o
j
!
P]
@
> 5 through 9
¤
H[
Y
f
†
*
Except when used as a matrix function.

f uses the LAST X register in a special way, as described in appendix E.