HP 48gII Advanced User's Reference Manual page 46

FOR takes start and finish from the stack as the beginning and ending values for the loop counter, then creates
the local variable counter as a loop counter. Then the loop-clause is executed — counter can appear within the
loop-clause. NEXT increments counter by one, and then tests whether its value is less than or equal to finish. If
so, the loop-clause is repeated (with the new value of counter) — otherwise, execution resumes following
NEXT. When the loop is exited, counter is purged.
To enter FOR ... NEXT in a program:
Press !°%BRCH% ! %FOR%.
!
Example: The following program places the squares of the integers 1 through 5 on the stack:
« 1 5 FOR j j SQ NEXT »
Example:
The following program takes the value x from the stack and computes the integer powers i of x. For
example, when x =12 and start and finish are 3 and 5 respectively, the program returns 12
requires as inputs start and finish in level 3 and 2, and x in level 1. ( x removes x from the stack, leaving start
and finish there as arguments for FOR.)
«  x « FOR n 'x^n' EVAL NEXT » »
The FOR ... STEP Structure
The syntax for this structure is
« ... start finish FOR counter loop-clause increment STEP ... »
FOR ... STEP executes the loop-clause sequence just like FOR ... NEXT does — except that the program
specifies the increment value for counter, rather than incrementing by 1. The loop-clause is always executed at
least once.
1-20 RPL Programming
Syntax
Start
finish
FOR
loop-clause
NEXT
FOR ... NEXT Structure
Flowchart
1:Start
2:finish
counter=start
Store finish
Body of loop
counter = counter + 1
Is
yes
counter finish?
no
3 4 5
, 12 and 12 . It