Drexel dragonThe Math ForumDonate to the Math Forum



Search All of the Math Forum:

Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.


Math Forum » Discussions » sci.math.* » sci.math.independent

Topic: Prime Digit Sums
Replies: 0  

Advanced Search

Back to Topic List Back to Topic List  
Hauke Reddmann

Posts: 532
Registered: 12/13/04
Prime Digit Sums
Posted: May 28, 2013 12:20 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

A MATHEMATICA oneliner:

ListPlot[Table[{k,Table[If[PrimeQ[Total[IntegerDigits[i,k]]],i,0],
{i,1,10000}]//Union//Length},{k, 2, 100}]]

It counts the numbers whose (noniterated) digitsum (base k) is prime.
I limited the numbers to <10000 to get a result in decent time.
The values are extremely high - even base 100 over 2000 numbers
qualify. Insert joke about drowning number theoretican? :-)

What would you expect as O(k)?
--
Hauke Reddmann <:-EX8 fc3a501@uni-hamburg.de
Das Licht vorm Fensterladen blinkt
Hotel Hotel Hotel
Reiß ihn auf und träum im Mondlicht



Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© Drexel University 1994-2014. All Rights Reserved.
The Math Forum is a research and educational enterprise of the Drexel University School of Education.