Date: May 28, 2013 12:20 PM
Author: Hauke Reddmann
Subject: Prime Digit Sums

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
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