Fascinating. Contrary to what I said at Re: Re (tilly) 1: Rotationally Prime Numbers, when I consider numbers that are strings of 1's, the prime number theorem naively suggests that there should be an infinite number of rotational primes of that form. (This differs from most numbers in that there is only 1 number in the rotation - the odds of 1 number being prime is far different than the odds of n of them being prime.)

Of course there are a lot of special factorization properties of long strings of 1's. So it may not be so simple as all that. But the number of rotational factors between length 23 and 1031 matches the naive prediction surprisingly well. (The naive prediction is that the number of primes out to length n should be roughly log(n)/log(10), and the number in any interval should be the difference of those two. From 23 to 1031 we'd predict 1.65 and actually had 2.)

In reply to Re^2: Rotationally Prime Numbers Revisited by tilly
in thread Rotationally Prime Numbers Revisited by Limbic~Region

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.