A quick video: https://www.quantamagazine.org/the-number-15-describes-the-secret-limit-of-an-infinite-grid-20230420/ https://www.quantamagazine.org/the-number-1

A quick video: https://www.quantamagazine.org/the-number-15-describes-the-secret-limit-of-an-infinite-grid-20230420/ https://www.quantamagazine.org/the-number-15-describes-the-s... > distance “apart” refers to something called their “taxicab distance,” meaning you only squares between numbers in straight lines along paths made of right angles. I'd only ever heard of this distance being referred to as the Manhattan distance. https://xlinux.nist.gov/dads/HTML/manhattanDistance.html https://xlinux.nist.gov/dads/HTML/manhattanDistance.html https://en.wikipedia.org/wiki/Taxicab_geometry https://en.wikipedia.org/wiki/Taxicab_geometry