# 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.

### 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