Sacks Spiral of Prime Numbers

 

(Image: Claudio Rocchini/Wikimedia Commons CC-BY)

This blog has had prior posts about spirals of prime numbers - see: Prime Number Spirals and Ulam Spiral.

Another variant of the Ulam Spiral is the Sacks Spiral, developed by Robert Sacks in 1994 and is shown above. It is constructed so one perfect square occurs in each full rotation. In the Ulam Spiral, two perfect squares occur in each rotation. 

The graphic was found in an article in Science, 29 July 2024 describing advances in trying to prove the Riemann Hypothesis (one of the remaining unsolved Hilbert Problems).