Article: 4997 of comp.sys.handhelds
From: kskalb@faui1f.informatik.uni-erlangen.de (Klaus Kalb)
Subject: HP48: Factoring Integers
Date: 21 Dec 90 15:36:54 GMT

This routine factors integers into primes.
The program does trial division by all numbers that
are not true multiples of 2,3,5 or 7.
The main work is done in mcode, so it is fast.
You need ASC\-> to install it.  [No you don't.  Already installed.  -jkh-]

Happy Christmas and a merry new year,
-KK

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                         Author
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  Mail any suggestions or comments to

                 kskalb@informatik.uni-erlangen.de

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                         Usage
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    Input:
      Level 2: Number n to be factored (binary or real; n < 2^63)
      Level 1: Bound  b (binary or real; b < 2^20)

    Output:
      Level 1: List of Factors 

If the program is sure that all numbers in the output list are indeed
primes, the list will be tagged with a plus-sign.

If the tag is missing, the last entry in the list might not be a prime.

All divisors t of n with t<=b will be found.

The entries in the result will be real, unless they are greater than 2^39.
Note that this can only happen to the last number in the list.

[Note: See FACTOR for application of Klaus' code.  -jkh-]

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                         Installation
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[Note! This applies ONLY to the original source code, TRIAL.SRC; the TRIAL
 program on the disk is already "installed" and may be used directly, so you
 may ignore what follows.  -jkh-]

  -- Download the following program to your HP48.
  -- Be sure that ASC/-> is accessible.
  -- Evaluate the downloaded object.
  -- A program named 'TRIAL' will appear on the current directory.


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                         Warning
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  The program 'TRIAL' contains a code object.
  To my knowledge, programs containing code object can't be
  edited on the HP48 by standard means, so don't try it.

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                         Disclaimer
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     This program makes use of undocumented low-level features of
     the HP48SX calculator, and may or may not cause loss of data,
     excessive battery drainage, and/or damage to the calculator
     hardware.  The Author takes no responsibility whatsoever for 
     any damage caused by the use of this program.

     This software is provided "as is" and WITHOUT ANY EXPRESS OR
     IMPLIED WARRANTIES, including, but not limited to, THE IMPLIED
     WARRANTIES OF MERCHANTABILITY and FITNESS FOR A PARTICULAR PURPOSE.

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   Klaus Kalb    | mail :  IMMD1 / Martenstr. 3 / W-8520 Erlangen / Germany   
                 | email:  kskalb@immd1.informatik.uni-erlangen.de   
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