Loading ...
Sorry, an error occurred while loading the content.

Extended Ulam Spiral

Expand Messages
  • miltbrown@earthlink.net
    I have extended the Ulam Spiral by starting with a prime number (at the center). Then a large number of primes are on the NW corner values. For 101 at the
    Message 1 of 2 , Jun 4, 2009
    • 0 Attachment
      I have extended the Ulam Spiral by starting with
      a prime number (at the center). Then a large
      number of primes are on the NW corner values.
      For 101 at the center yields the numbers:

      101,103,113,131,157,191,233,283,(341),(407),(481),
      563,653,751,857,971,1093,1223,1361,(1507)

      yielding 16/20 primes

      The formula is 4n^2-10n+107

      Milton L. Brown
      miltbrown@...
    • miltbrown@earthlink.net
      Following are the ratios of primes to total for Extended Ulam Spiral 107: 30 .8 40 .78 50 .72 60 .67 70 .63 80 .65 90 .63 100 .64 110 .63 Does this
      Message 2 of 2 , Jun 5, 2009
      • 0 Attachment
        Following are the ratios of primes to total

        for Extended Ulam Spiral 107:

        30 .8

        40 .78

        50 .72

        60 .67

        70 .63

        80 .65

        90 .63

        100 .64

        110 .63

        Does this remain above 50% ?

        I would call {n =1..., 4n^2-10n+107} a dense set of primes?

        Milton L. Brown

        miltbrown@...
      Your message has been successfully submitted and would be delivered to recipients shortly.