Reference - HP 48gII User Manual

OCT(al), or BIN(ary) in the BASE menu. For example, if @HE
binary integers will be a hexadecimal numbers, e.g., #53, #A5B, etc. As
different systems are selected, the numbers will be automatically converted to
the new current base.
To write a number in a particular system, start the number with # and end
with either h (hexadecimal), d (decimal), o (octal), or b (binary), examples:
[Note: not all lines will be visible when done with the exercises in the
following figures.]
HEX
OCT

Reference

For additional details on numbers from different bases see Chapter 19 in the
calculator's user's guide.
DEC
BIN
is selected,
!
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