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One Year of Sponsored Servo Development

https://servo.org/blog/2026/09/15/one-year-of-sponsorship/
163•AshleysBrain•4h ago•73 comments

Neovim have a ~$800k Bitcoin donation sitting untouched since 2023

156•jakemanger•1h ago•43 comments

Nvidia announces native GPU programming in Rust

https://developer.nvidia.com/blog/introducing-cuda-rust-two-tracks-for-writing-gpu-kernels/
763•nonmaskable•1d ago•308 comments

Better Vector Search for Long Documents: Chunking Inside Manticore Search

https://manticoresearch.com/blog/auto-chunking/
28•GloriaVinogrado•2h ago•1 comments

My temporary PHP fix from 2014 has nearly 20M installs. Today I'm deprecating it

https://jakeasmith.com/blog/http-build-url/
170•jakeasmith•1d ago•42 comments

Keys Not Included: recovering the signing keys for US driver's license barcodes

https://ryan.science/blog/keys-not-included
208•Ryan5453•9h ago•74 comments

The Relation Between Mathematics and Physics by Paul Dirac

https://www.damtp.cam.ac.uk/events/strings02/dirac/speach.html
89•rramadass•3d ago•27 comments

GLM Built Its Own Inference Infrastructure

https://z.ai/blog/glm-built-its-inference-infrastructure
134•whiteros_e•4h ago•98 comments

Training a 4B model to produce 81% faster query plans than Postgres

https://rohanbansal.com/qorl
586•polyphilz•17h ago•121 comments

Online Z3 Guide

https://microsoft.github.io/z3guide/
25•Bluestein•1d ago•6 comments

CCC invites all model citizens to 40C3

https://events.ccc.de/en/2026/09/12/40c3-model-citizens/
31•antonly•4h ago•0 comments

Xiaomi Mimo 2.6 live post-training dashboard

https://mimo.xiaomi.com/rl/
468•krackers•16h ago•135 comments

Lucasart's Afterlife

https://togameforlife.wordpress.com/2023/12/09/on-lucasarts-afterlife/
45•Bondi_Blue•1d ago•19 comments

Small programming tricks

https://will-keleher.com/posts/small-programming-tricks-matter/
567•signa11•20h ago•251 comments

Comparison of Malloc() Algorithms

https://egbert.net/blog/articles/comparison-of-arena-architecture-in-malloc.html
88•egberts1•1d ago•22 comments

Developing provably correct Rust code with Verus

https://www.amazon.science/blog/developing-provably-correct-rust-code-with-verus
129•Betelbuddy•2d ago•24 comments

Breaking the 1.58-bit Barrier for Ternary LLMs

https://arxiv.org/abs/2609.16338
216•matt_d•15h ago•34 comments

Cloudflare/Security-Audit-Skill

https://github.com/cloudflare/security-audit-skill
100•donk8r•8h ago•18 comments

Show HN: An e-ink frame that hears birds and draws them as 1800s illustrations

https://github.com/arnegiacomo/fugleramme
2195•arnemunthekaas•2d ago•245 comments

An Archive of Colour Gradients

https://phillips.shef.ac.uk/pub/cpt-city/
14•ashitlerferad•3d ago•2 comments

Backups Aren't Simple

https://filipovski.net/2026/09/16/backups-arent-simple.html
271•afilipovski•16h ago•169 comments

A 32-year-old bug walks into a Telnet server

https://labs.watchtowr.com/a-32-year-old-bug-walks-into-a-telnet-server-gnu-inetutils-telnetd-cve...
70•paimapi•1d ago•30 comments

PCB is brought to you by Fable 5

https://a6mzero.com/posts/this-pcb-is-brought-to-you-by-fable-5/
129•jasonpeacock•3d ago•59 comments

AWS says it can't restore some data from mideast facilities struck by Iran

https://www.wsj.com/world/middle-east/aws-says-it-cant-restore-some-data-from-mideast-facilities-...
449•berkeleyjunk•1d ago•376 comments

The engineering behind the US Strategic Petroleum Reserve

https://johnjwang.com/post/2026/09/15/engineering-behind-us-strategic-petroleum-reserve
225•johnjwang•1d ago•91 comments

HarnessTax: How Much Does the Harness Matter for Coding Agents?

https://harnesstax.github.io/
151•matt_d•14h ago•59 comments

OpenSpec – A lightweight and configurable AI spec framework

https://openspec.dev/
158•etoxin•13h ago•72 comments

Performance Improvements in .NET 11

https://devblogs.microsoft.com/dotnet/performance-improvements-in-net-11/
309•soheilpro•2d ago•82 comments

Japan's book scene is moving from bookstores to libraries

https://untranslatedjp.substack.com/p/japans-book-scene-is-quietly-moving
212•herbertl•4d ago•86 comments

Reversing Factorio's RNG

https://gegell.github.io/posts/factorio-rng/
223•jheitmann•4d ago•41 comments
Open in hackernews

Right-Truncatable Prime Counter

https://github.com/EbodShojaei/Right-Truncatable-Primes
9•rainmans•1y ago

Comments

throwawaymaths•1y ago
Curious about base 2. Obviously if you hit a 0 it's immediately not prime, but maybe adjust the rules so:

- you drill through as many 0's on the right.

- you finish on 1.

3, 5, 7, 11, 13, 15, 17 are all right truncatable, 19 is the first non-truncatable prime in this scheme.

nh23423fefe•1y ago
i dont think smaller radixes make the problem more interesting. the problem is interesting because base 10 has a large branching factor
throwawaymaths•1y ago
I think in the base2 reformulation I propose we do not know for certain if the list of numbers terminates, as all Fermat primes are in the set and we don't know if there are infinitely many Fermat primes.

For base-10 and the original rules the set is provably closed.

"Drilling through zeros" makes the branching unbounded.

jinwoo68•1y ago
There's a Project Euler problem for finding truncatable prime numbers, from both left and right: https://projecteuler.net/problem=37
thechao•1y ago
Just in case any else is wondering: there are only 83 right-truncatable primes (RTP) and that is it. There's two constraints that let you see this "immediately":

1. An RTP must start with {2,3,5,7,9}; and,

2. An RTP must end with {1,3,7,9}.

So, let's take the largest RTP (73939133) and try to "extend" it: there are only four possible extensions: 73939133[1], 73939133[3], 73939133[7], 73939133[9]. None of these are prime. This holds for the other 8-digit RTPs. Therefore, there is no extension to a 9-or-longer RTP. Thus, the list is exhaustive.