I'm a sixth-form student in the UK. I like mathematics and building software that proves its own results — the kind where you can check the claim yourself instead of taking my word for it. That one idea runs through everything here: a puzzle generator that must prove a puzzle sound before emitting it, a consensus protocol whose safety properties are machine-checked, a renderer validated against what the physics predicts, and new terms for the OEIS that ship with their certificates.
I have been computing new terms in families of mixed van der Waerden numbers whose OEIS entries were last extended by Tanbir Ahmed in 2012 and were still unchanged when I checked them against the OEIS API on 29 July 2026.
For colour targets t_1..t_r and a budget of j wildcards,
w(j+r; 2^j, t_1..t_r) = 1 + max{ n : [1,n] splits into j singleton classes and
r colour classes, where colour class i contains
no t_i-term arithmetic progression }
Each new term needs two independent halves. The lower bound is a colouring, and a colouring is a certificate — you read the string and apply the definition, no solver involved. The upper bound asserts that no colouring exists, which is only as trustworthy as the encoding behind it, so that half is where the work is.
Status, stated exactly.
- Five new terms established across five families, each shipping evidence alongside the claim rather than a solver's word for it.
- All five are in the OEIS, approved between 6 and 13 August 2026: A217058 a(12) = 57, A217005 a(19) = 52, A217007 a(7) = 68, A217236 a(4) = 84 and A217059 a(9) = 74.
- The headline refutation is reduced to formally checked proof objects — 4,487
per-cube DRAT proofs, each replayed to
s VERIFIEDbydrat-trim, plus a checked proof that the cube set is exhaustive. The other four upper bounds rest on cross-checked solver verdicts rather than on checked proofs, and the write-up says exactly that.
Method, encoding, symmetry breaking and the limits of what has actually been proved are written up in MathRecords. The standalone certificate verifier depends on nothing but the Python standard library.
Roughly one idea, applied repeatedly: a result is worth what its verification is worth. Each of these is public, and each is built so that what it claims can be checked rather than believed.
- QuantumCompiler — a compiler for quantum circuits, its transformations stated as properties that are tested rather than asserted.
- DeterministicRaft — an implementation of the Raft consensus protocol whose safety properties are machine-checked under deterministic simulation, so a violation reproduces from a seed instead of appearing once and vanishing.
- Splitbrain — a distributed-systems test harness in Go that drives a real key-value cluster through seeded network partitions and machine-checks whether what the clients saw was even possible, with the linearizability checker validated against a brute-force oracle.
- Osmium — an operating system for x86_64, written from scratch in Rust. It boots on BIOS and UEFI and preemptively schedules user programs in ring 3, each in its own address space, with fault isolation proven in CI by a program that page-faults beside a healthy one and is terminated alone; its privacy properties are enforced by boot-time self-tests rather than promised — no network stack exists and freed memory is zeroed, both checked on every push.
- PathTracer — a physically based renderer written with no dependencies, validated against what the physics predicts in advance.
- QuantumClaimReferee — a checker for statistical claims, aimed at the gap between a number being computed and a number being meaningful.
- ChessPuzzleForge — chess tooling: an engine, an analyser, and a puzzle generator that must prove a puzzle sound before it will emit it.
- TerminalAgent — a terminal-based agent, built around the question of what such a thing should refuse to do.
- EndeavourRacing — the web applications for a student motorsport team: the marketing site, a lap-time prediction tool, and a project, risk and budget dashboard.
- TradingEngineResearch — the research core of a systematic trading platform: a fail-closed engine, a default-deny validation gate, and a pre-registered alpha search whose honest result was negative.
- MeltSim — an interactive thermodynamics sandbox: enthalpy-method melting, solidification and boiling in the browser, with zero runtime dependencies.
- IaCScanner — an offline infrastructure-as-code misconfiguration scanner: Terraform, Kubernetes, Actions and Dockerfile rule packs, SARIF output, and a fail-only-on-new CI baseline.
- DocRedact — a local-first, policy-driven document redaction CLI that never sends a document anywhere.
- VisionCheckR — a privacy-first educational vision self-check that runs entirely in the browser, with a pure, unit-tested scoring core. Not a medical device.
- Understudy — an interview rehearsal studio that runs entirely in the browser: on-device face and speech analysis with an annotated replay of your answer. The privacy claim is enforced rather than promised — a CI test records a real session and fails the build if any request leaves the origin. Live at leo-y-zhang.github.io/Understudy.
- ClimateMesh — a Raspberry Pi environmental sensing mesh with explainable early-warning risk scoring, built by two sixth-form students for the PA Raspberry Pi Competition 2026.
- FireTurret — a camera-guided fire-suppression turret demonstrator: simulation, vision and safety interlocks behind one supervised control loop, with the safety case written down.
- FilingsLab — an SEC-filings event-study backtester: disclosure ingestion, deflation-robust validation, and a research loop that must prove an edge before believing it.
Some work stays private: a live web application with real users, and the live-trading side of the platform whose research core is published above. Neither is private for want of finishing.
Mostly Python and TypeScript, with SAT solvers, DRAT/LRAT proof checking, and whatever numerical method the problem happens to need.
The same machine-checkable approach applied to other integer sequences.
GraphRecords turns bishop
arrangements into rook arrangements and has put fourteen new terms into seven
OEIS sequences on board graphs.
RadoRecords carries the 2-colour
Rado numbers for x_1^2 + ... + x_n^2 = z^2 from a(30) to a(60) with
DRAT-certified refutations — a(31) approved, the rest a proposed draft awaiting
an editor as I write this.
Refute is the second opinion on those
certificates: an independent DRAT/LRAT checker in Rust, with a browser
playground where the files never leave the tab.
Contact: open an issue on any repository here.