There's a story about this spiral way of writing the whole numbers. I think it's called "the Ulam spiral" after a guy called Stanislaw Ulam who was sitting a math lecture one day, and it was a bit boring, so he wasn't really listening. He just started with your first spiral of the numbers 1,2,3,4,5,... going around the central point and spiraling outwards. Then he shaded in the prime numbers and he noticed something, which is that there were several diagonal lines on a kind of diamond-shaped grid pattern, which had far more primes on them than all the others. So he wrote down a recursive formula for those lines and they allowed him to find a lot of prime numbers very quickly, because the prime numbers were more dense on those lines than they are on the number line. Check "Ulam spiral" on Wikipedia to see some computer drawings. There's also a version with a triangular spiral with vertical lines of primes that was discovered earlier. And there are hexagonal ones too.
... and his posterity too? See On Communication in Linear Time And Hypertext And The Gospel of Sophia . So it looks like El Cielo of the cistine [sic!😂] chapel is not the limit anymore. I think I just met one of his descendents. A guy called Versailles Toledo who is from Chiapas. That might explain the murals I mention in my recent untitled post , just before the post mentioning this video. I also just took this photo of Rafael Gonzales, born here in Tecate, B.C., who told me about a spring near here called Agua Fría , half way from Tecate to Loma Tova , where, a few decades ago, people used to go to have barbecues and stuff, but now he thinks it may be private land. If someone reading this has a Facebook account, please write a link to this post onto his FB page. To see why I took the photo, look at his T-shirt and the horse-shoes and ponder this: Subscribe to BeatrizER and her video(s?) about mathematical logic, ... Sounds like Edith (II) Rix has been online all the t...
This was in The Guardian: David Turner obituary , only eight days after I posted David Turner Talking About Sixty Years of Functional Programming History : This talk was given in London in 2017: See Turner, D. A. "Some History of Functional Programming Languages" also John Hughes - Why Functional Programming Matters and David MacQueen's talk at ICFP 2015 in Numberphile - Sophie Maclean on the Catalan Numbers . At 10:30 This whole discussion abut combinator reduction is especially interesting. I didn't know Arthur Norman had tried building hardware for combinator machines. I'll look that up: maybe start here A.C. Norman Faster combinator reduction using stock hardware in LFP '88: Proceedings of the 1988 ACM conference on LISP and functional programming. At 26:25 on the ISWIM virtual machine implemented in the PAL compacting garbage collector?! This work Reynolds and others did was at MIT in Masecheusetts and Argonne National Laboratory ...
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