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The nth harmonic number is the sum of the reciprocals of the first n positive integers. Hn = 1 + 1/2 + 1/3 + 1/4 + … + 1/n The product of all the denominators is n!, so you could write Hn as a fraction Hn = p/q where p = n! Hn is an integer and q = n!. While […]

The post Writing down harmonic numbers first appeared on John D. Cook.

Stating the obvious is surprisingly useful. Most of your knowledge lives below the threshold of conscious awareness, so it’s possible for a piece of writing to remind you of what you already know. It’s common to know you don’t like something without being quite sure why, and...

Data is from 2026-06-20. North is right. 0.53"/pixel (27'x27' field). FWHM=4' A nice, if rather small (~100") edge on spiral galaxy. Arp filed this one under "low surface brightness companions", but the companion doesn't seem to exist. There's a bright spot to the...

June is not over, and anything could still happen, but a lot already has.

This is a bad state of affairs. Consider, in particular, some industry dynamics: Frontier models are trained at an enormous cost, and a significant fraction of that cost is recouped in the few post-release months that they are broadly available. After that period elapses, ...

This is like saying there's no learning curve to being a manager because your employees will just do whatever you tell them to do.

— Timothy B. Lee, on the idea that LLMs take no skill and have no learning curve

Tags: llms, ai, generative-ai

What happened after 2,000 people tried to hack my AI assistant Fernando Irarrázaval ran a challenge on hackmyclaw.com to see if anyone could leak secrets held by his OpenClaw test instance by sending it email. Surprisingly, after 6,000 attempts (and $500 in token spend and a...

Incident Report: CVE-2026-LGTM

Spectacular hypothetical incident report by Andrew Nesbitt.

Day 2, 16:00 UTC --- Two AI review agents from competing vendors, both attached to a downstream pull request bumping foxhole-lz4, enter a disagreement loop over whether the package is malicious. After 340 comments and $41,255 in inference spend, Finance revokes both API keys; one vendor's marketing team, cc'd on the cost anomaly alert, issues a press release citing "a 430% YoY increase in adversarial multi-agent security reasoning." The stock opens up 6%.

Tags: security, ai, prompt-injection, generative-ai, llms, supply-chain, ai-security-research, andrew-nesbitt

We're beginning a limited preview of the GPT‑5.6 series: Sol, our flagship model; Terra, a balanced model for everyday work; and Luna, a fast and affordable model. Terra has competitive performance to GPT‑5.5 while being 2x cheaper and Luna brings strong capability at our l...

Or human-ish

Opus 3: Henry VI, Part 2

Labs are throwing away the most valuable data.

I'm not paying seventy bloody quid for an official PS5 controller - so I found a knock-off version for a smidge under £40. And this one has lots of unnecessary blinkenlights! Gamrombo is the consumer-facing brand of the generically named Professional Controller Manufacturer. AKA "Huizhou Ronghui Technology Co., Ltd" - there's virtually no information about them online other than paid-for …

Quick: Who was the first browser manufacturer to hold an IPO in the dotcom era? Netscape? WRONG! Its competitor Spyglass beat it out, holding its IPO June 27, 1995. Its IPO did rather well too, issuing two million shares at

The post Spyglass: A web browsing pioneer’s IPO appeared first on The Silicon Underground.

A series of unfortunate agents.

This is a quick post, mostly for my own reference.

I've avoided LUTs and 'Log' video footage for years¹, mostly because of the extra tiny bit of workflow involved. Like RAW photos, 'Log' footage retains the video sensor's full dynamic range, so you can pull more color and luminance information out of the footage later.

But unlike photography, where RAW has been a thing for decades, and many workflows 'just work' without me having to 'grade' every individual photo, in video precious few consumer apps handle Log footage gracefully. You generally end up with a muddy grey mess.

If you have’t heard, Om Malik passed away. People are sharing stories of their graceful encounters with him. This one is mine. Back at the beginning of 2021, I set a goal to write 72 blog posts. I was puttering along, publishing whatever came to mind, mostly figuring that n...

Last week, I posted a visual demonstration of the sameness of AI-generated content.

Last week, I posted a visual demonstration of the sameness of AI-generated content.

Many people claim that AI inference is unprofitable to serve, and thus must be subsidized by an ocean of dumb money from investors who believe that some future AI model will come to dominate the world economy. When that dumb money goes away, so will AI products. According to...