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Comment on The Ulam spiral: hidden structure among the prime numbers

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Arthur C. Clarke described the prime spiral seven years before it was discovered by Ulam in his 1956 novel 'The City and the Stars': "Jeserac sat motionless within a whirlpool of numbers. The first thousand primes, expressed in the binary scale that had been used for all arithmetical operations since electronic computers were invented, marched in order before him. Endless ranks of 1's and 0's paraded past, bringing before Jeserac's eyes the complete sequences of all those numbers that possessed no factors except themselves and unity. There was a mystery about the primes that had always fascinated Man, and they held his imagination still. Jeserac was no mathematician, though sometimes he liked to believe he was. All he could do was to search among the infinite array of primes for special relationships and rules which more talented men might incorporate in general laws. He could find how numbers behaved, but he could not explain why. It was his pleasure to hack his way through the arithmetical jungle and sometimes he discovered wonders that more skilful explorers had missed.

He set up the matrix of all possible integers, and started his computer stringing the primes across its surface as beads might be arranged at the intersections of a mesh. Jeserac had done this a hundred times before and it had never taught him anything. But he was fascinated by the way in which the numbers he was studying were scattered, apparently according to no laws, across the spectrum of the integers. He knew the laws of distribution that had already been discovered, but always hoped to discover more."

Aside from him visualizing primes using the word "whirlpool", that doesn't sound like the same thing at all. For one, the Ulam spiral doesn't employ binary representation. And it distinctly presents a diagonal pattern, whereas Clarke seems to be describing a visualization with no patterns at all ("apparently according to no laws").

I love the fact Clarke used the term "hack" in 1956.

I'd just like to double-check that you and others realise that there are multiple definitions for the word "hack," some originating from far before the 1950s ;)

chop: cut with a hacking tool

cut away; "he hacked his way through the forest"

a mediocre and disdained writer

etc.

http://www.google.com/search?sourceid=chrome&ie=UTF-8...

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