ulam_spiral


ulam_spiral, a Python code which displays the integers as a spiral of grid cells, with the primes highlighted, so show that they tend to fall along diagonals, as discovered by Stanislaw Ulam.

Licensing:

The computer code and data files described and made available on this web page are distributed under the MIT license

Languages:

ulam_spiral is available in a MATLAB version and an Octave version and a Python version.

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Reference:

  1. Martin Gardner,
    Mathematical Games: The Remarkable Lore of the Prime Number,
    Scientific American,
    Volume 210, March 1964, pages 120-128.
  2. Martin Gardner,
    Sixth Book of Mathematical Diversion from Scientific American,
    ISBN13: 978-0-226-28250-3,
    University of Chicago Press, 1971.
  3. Christian Hill,
    The Ulam Spiral,
    https://scipython.com/blog/the-ulam-spiral/
  4. Cleve Moler,
    primespiral.m,
    Numerical Computing with MATLAB,
    SIAM, 2004,
    ISBN13: 978-0-898716-60-3,
    LC: QA297.M625,
    ebook: https://www.mathworks.com/moler/chapters.html

Source Code:


Last modified on 21 August 2023.