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cbrighton Tell HN: GpuOwl/PRPLL, GPU software used to find the largest prime number

The PRP test has the same computational cost as an LL test. The reason why GIMPS now prefers to do PRP tests instead of LL tests is because an efficiently verifiable proof-of-work certificate was developed for PRP tests [1].

[1] https://doi.org/10.4230/LIPIcs.ITCS.2019.60

cbrighton How Large is a 160 Bit Number?

2^80 is about 10^24, which is a trillion trillion, not a billion trillion. So their estimate of a chance of a collision is off by a factor of 1000.

cbrighton How hard can generating 1024-bit primes be?

> But I don't know if it can be proven there do not exist non-prime P/Q values which produce an RSA keypair which can successfully encrypt/decrypt messages. I'm sure this isn't kosher for a real implementation, but I've never found an answer.

If p and q are coprime Carmichael numbers then RSA will still successfully encrypt and decrypt messages, though this will be less secure as p*q will have smaller prime factors and thus be easier to factor.

cbrighton Computation of the n'th digit of pi in any base in O(n^2) (1997)

> this post refers to it as reference 2. That algorithm runs in constant time, which is a pretty big deal.

Not constant time; the analysis in the paper shows that the nth digit can be computed in O(n log n M(log n)) bit operations, where M(j) is the bit complexity of multiplying two j bit numbers.

cbrighton Counterintuitive Properties of High Dimensional Space (2018)

Yes, the volume of the unit cube is 1 in any dimension, but the volume of the unit sphere goes to 0 as the dimension increases.

cbrighton Hipmunk Says Goodbye

"Any time a company gets acquired, there are always concerns about what it means for the company and product. Here are some things to know:

1. Hipmunk isn’t going anywhere"

-Adam Goldstein, October 3, 2016

cbrighton Effective problem solving using SAT solvers

It's cool seeing this posted here, I authored this paper. The inspirational quote at the beginning was actually from a comment on a HN post a month ago: https://news.ycombinator.com/item?id=19953213

cbrighton Ubuntu Bug 255161: Openoffice can’t print on Tuesdays

It's interesting to follow some of abrianb's comments by date:

"When I click print I get nothing." -Tuesday, August 5, 2008

"I downloaded those updates and Open Office Still prints." -Friday, August 8, 2008

"Open Office stopped printing today." -Tuesday, August 12, 2008

"I just updated and still print." -Monday, August 18, 2008

"I stand corrected, after a boot cycle Open Office failed to print." -Tuesday, August 19, 2008

cbrighton Hudson's Lost Mario Trilogy (2010)

That's just a remake of the classic Mario Bros.; there's no punch ball in SMB3.

cbrighton [dead]

> Who knows what bugs wait lurking in there; who knows which particular combinations of which libraries are a security-bug timebomb. [...] The GTK and GNOME libraries have never been security-audited to the extent that their maintainers would be willing to make the claim, "under no circumstances will this library ever crash."

> gnome-screensaver is brand new, bug-ridden, unreliable, and a security disaster waiting to happen

Looks like jwz has been vindicated here.

References: http://www.jwz.org/xscreensaver/toolkits.html http://www.jwz.org/xscreensaver/faq.html#gnome-screensaver

cbrighton 0^0

Correction: x^y is defined for all pairs of real numbers with x!=0. 0^x is not defined for negative x.

cbrighton Facebook to overtake Google in the next 18 months

"Whenever you're told that some existing statistical trend will continue, but you aren't given a hard-to-vary account of what causes that trend, you're being told a wizard did it." -David Deutsch