Simon Willison’s Weblog

Largest known prime number (via) Discovered on 12th October 2024 by the Great Internet Mersenne Prime Search. The new largest prime number is 2^136279841-1 - 41,024,320 digits long.

Posted 2nd January 2025 at 7:39 am

Recent articles

The Summer of Johann: prompt injections as far as the eye can see - 15th August 2025
Open weight LLMs exhibit inconsistent performance across providers - 15th August 2025
LLM 0.27, the annotated release notes: GPT-5 and improved tool calling - 11th August 2025

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