[VA] New updates available in my HP site [Latest is Update #39, Sep 22]

[Valentin Albillo]

      
Hi, all:

After the summer vacations and as today it's Sep, 5th and I recently posted my 555th message to the forum, I've just made available Update #20 at my HP site, namely the following 8 files (this makes 570 files in all which you can see and/or download for free):

• Note: I'll appreciate it if very much if you would please refrain from posting anything to this thread, so that it only contains the update announcements and listings themselves and nothing else. If you want to comment something please create another thread or PM me for any questions or comments you want addressed. Thanks.

     
2020-09-05:   Update #20   (8 files, including one new Article):

       HP Article VA046 - Boldly Going - Abundant but Rare.pdf  (click to see or download)  in HP Calculator Articles

• 7-page article belonging to my “Boldly Going” series, this time dealing with a most fascinating topic in Number Theory, namely finding a particularly rare kind of so-called abundant numbers.
  
  The qualifier “abundant” refers to a classification of the positive integers which considers them as being either deficient, perfect or abundant depending on the sum of their proper divisors, and we’re boldly going to find a most rare variety of the latter, so rare in fact that up to 10²¹⁰ there are only seven of them, A₁ to A₇, the last one being a 205-digit number no less.
  
  Anyway, my trusty vintage HP-71B quickly finds and display all seven, exactly. This article also features a very useful 5-line user-defined function to compute the "Sum of Proper Divisors" number-theoretical function and two variants, including several interesting examples of use.

       
And last but not least, there's also (click on any of them to see or download):

3 Selected HP Threads:

      HP Thread VA034 - 2003-11-11 - Humor Eavesdropping at KinHPo.pdf
      HP Thread VA035 - 2003-11-11 - Your Favourite Calculator.pdf
      HP Thread VA036 - 2003-11-15 - What is your OWN favorite RPN program.pdf

4 Selected FractVal images:

      Misc Picture VA211 - Interference - VF171202AO.jpg
      Misc Picture VA212 - Distorting Spacetime - VF180118AE.jpg
      Misc Picture VA216 - Neutrino Trap - VF180327AA.jpg
      Misc Picture VA221 - Magnetic Dipole - VF180121AH.jpg

V.