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nsomani

Show HN: GPT-Erdos – the results of GPT 5.2 Pro on the Erdos problems

https://www.ocf.berkeley.edu/~neel/erdos.html

Hi HN, it seemed like there was broad interest in the previous Erdos problem that GPT 5.2 Pro solved: https://news.ycombinator.com/item?id=46664631I recruited a team of smart undergraduates to construct a dataset of ChatGPT responses to every open Erdos problem and verify the output.They found:- 3 problems with new proofs (though in 2 cases, historical partial results were found that could be...

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Appreciate that. I didn't realize how derivative this was when I built it! I was just trying to build something cool with the Codex SDK.
They cannot edit the iFrame itself. The user is allowed to edit the contents within the iFrame.
The Codex agent is only given tools to edit the single HTML file that displays on the homepage. The page is on a separate domain, so there's no cookie sharing, and the iFrame is in a sandbox. That said, the biggest risk is social engineering attacks.
Hi HN, I built this side project earlier this week. It executes an English auction on Solana with a reserve price of 0.1 SOL. Auction losers get refunded (minus a <$0.01 processing fee). The Codex agent operates in a sandbox and can only output HTML/JS/CSS.

The project is open-source: https://github.com/neelsomani/the-daily-auction

There are two examples provided - quote matching and bracket closing.

Show HN: Symbolic Circuit Distillation: prove program to LLM circuit equivalence

https://github.com/neelsomani/symbolic-circuit-distillation

Hi HN, I've been exploring various applications of formal methods to ML/interpretability and I've been hoping to get more eyes on the approach.I have been working on a small interpretability project I call Symbolic Circuit Distillation. The goal is to take a tiny neuron-level circuit (like the ones in OpenAI's "Sparse Circuits" work) and automatically recover a concise Python program that...

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Hi HN,

I have been working on a small interpretability project I call Symbolic Circuit Distillation. The goal is to take a tiny neuron-level circuit (like the ones in OpenAI's "Sparse Circuits" work) and automatically recover a concise Python program that implements the same algorithm, along with a bounded formal proof that the two are equivalent on a finite token domain.

Roughly, the pipeline is:

1. Start from a pruned circuit graph for a specific behavior (e.g. quote closing or bracket depth) extracted from a transformer. 2. Treat the circuit as an executable function and train a tiny ReLU network ("surrogate") that exactly matches the circuit on all inputs in a bounded domain (typically sequences of length 5–10 over a small token alphabet). 3. Search over a constrained DSL of common transformer motifs (counters, toggles, threshold detectors, small state machines) to synthesize candidate Python programs. 4. Use SMT-based bounded equivalence checking to either: - Prove that a candidate program and the surrogate agree on all inputs in the domain, or - Produce a counterexample input that rules the program out.

If the solver finds a proof, you get a small, human-readable Python function plus a machine-checkable guarantee that it matches the original circuit on that bounded domain.

Why I built this

Mechanistic interpretability has gotten pretty good at extracting "small crisp circuits" from large models, but turning those graphs into clean, human-readable algorithms is still very manual. My goal here is to automate that last step: go from "here is a sparse circuit" to "here is a verified algorithm that explains what it does", without hand-holding.

What works today

- Tasks: quote closing and bracket-depth detection from the OpenAI circuit_sparsity repo. - Exact surrogate fitting on a finite token domain. - DSL templates for simple counters, toggles, and small state machines. - SMT-based bounded equivalence between: sparse circuit -> ReLU surrogate -> Python program in the DSL.

Limitations and open questions

- The guarantees are bounded: equivalence is only proven on a finite token domain (short sequences and a small vocabulary). - Currently focused on very small circuits. Scaling to larger circuits and longer contexts is open engineering and research work. - The DSL is hand-designed around a few motifs. I am not yet learning the DSL itself or doing anything very clever in the search.

What I would love feedback on

- Are the problem framing and guarantees interesting to people working on mechanistic interpretability or formal methods? - Suggestions for next benchmarks: which circuits or behaviors would you want to see distilled next? - Feedback on the DSL design, search strategy, and SMT setup.

Happy to answer questions about implementation details, the SMT encoding, integration with OpenAI's Sparse Circuits repo, or anything else.

Hi all - this is a small research prototype I built to explore cross-GPU reuse of transformer attention states.

When inference engines like vLLM implement prefix/KV caching, it's local to each replica. LMCache recently generalized this idea to multi-tier storage.

KV Marketplace focuses narrowly on the GPU-to-GPU fast path: peer-to-peer prefix reuse over RDMA or NVLink. Each process exports completed prefix KV tensors (key/value attention states) into a registry keyed by a hash of the input tokens and model version. Other processes with the same prefix can import those tensors directly from a peer GPU, bypassing host memory and avoiding redundant prefill compute.

Under optimistic conditions (perfect prefix importing), the prototype shows about a 15% reduction in latency and throughput gains without heavy tuning. The code is intentionally minimal (no distributed registry, eviction, or CPU/disk tiers yet) but it's a prototype of "memcached for attention."

I thought others exploring distributed LLM inference, caching, or RDMA transports might find the repo useful or interesting.

Re:Show HN: Cuq – Formal Verification of Rust GPU Kernels on Thursday October 23, 2025 @04:55AM (#45679729)
Oh really? I can't find anything about the memory model online. I'm not sure what's the best way to do this, but if there's a way for us to get in contact, I'd be interested in adjusting the project so it's developed in the most ergonomic way possible. I'm chatting with a couple of universities and I might issue a research grant for this project to be further fleshed out, so would be keen to hear your insights prior to kicking this off. My email is neel[at]berkeley.edu.
Re:Show HN: Cuq – Formal Verification of Rust GPU Kernels on Wednesday October 22, 2025 @06:17PM (#45675866)
I think I've just spent too much time reading the word "CUDA" that I read "cu" as "koo", lol.
Re:Show HN: Cuq – Formal Verification of Rust GPU Kernels on Wednesday October 22, 2025 @05:55PM (#45675657)
That instinct is right. cuTile would be easier to parse but harder to reason about formally.
Re:Show HN: Cuq – Formal Verification of Rust GPU Kernels on Wednesday October 22, 2025 @05:54PM (#45675644)
Oh wow, honestly this caught me off guard - I've been pronouncing it "kook" in my head the whole time.
Re:Show HN: Cuq – Formal Verification of Rust GPU Kernels on Wednesday October 22, 2025 @03:39PM (#45674137)
Hi all, this is a small research prototype I built that connects Rust's MIR (Mid-level IR) to Coq, the proof assistant used for formal verification.

cuq takes the MIR dump of a Rust CUDA kernel and translates it into a minimal Coq semantics that emits memory events, which are then lined up with the PTX memory model formalized by Lustig et al., ASPLOS 2019.

Right now it supports:

* a simple saxpy kernel (no atomics)

* an atomic flag kernel using acquire/release semantics

* a "negative" kernel that fails type/order checking

The goal isn't a full verified compiler yet. It's a first step toward formally checking the safety of GPU kernels written in Rust (e.g. correct use of atomics, barriers, and memory scopes).

Happy to hear thoughts from folks working in Rust verification, GPU compilers, or Coq tooling.

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