Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.
Updated
Independent reviews of the Wang–Crapis route
locator_delta_review: Retains the 2026-09-07 affected-scope review that passed the twelve source-locator corrections the symbolic review required and carried its conditional verdict forward to the unchanged pages.
symbolic_review: Retains the 2026-09-07 independent mathematical and specification review of the nine result pages, card and PDF: conditional symbolic pass, forty-two finite certificates pending, one locator correction required.
The symbolic review records a conditional symbolic pass for the nine result pages and the selected PDF: the Wang–Crapis all- route is a complete symbolic derivation conditional on the forty-two declared pending finite certificates, four declared external premise classes and the separately accepted Cambie reuse. It required one bounded correction, twelve source locators in the lane's obligation table, before exact-byte acceptance.
The locator delta review records a scoped exact delta pass for that correction and carries the first verdict forward to the unchanged pages.
Both reviews were made by a fresh-context reviewer distinct from the author of the reconstruction, each on the frozen bytes it names. Neither is numerical execution credit: none of the forty-two finite rows is certified, the four external premise classes remain uncompiled, and no checker was read or run. Neither review alters the status of Problem 690. No distinct grader is recorded, so no tier is assigned.