{"id":"gcd-determines-valid-partition","text":"A deck of cards can be partitioned into equal-sized groups of matching values if and only if the GCD of all value frequencies is >= 2 — the solution computes this in a single `reduce(gcd, counts)` fold.","truth_value":"IN","source":"entries/2026/06/06/x-of-a-kind-in-a-deck-of-cards-solution.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"created_at":"","updated_at":"","reviewed_at":"","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"gcd-determines-valid-partition","truth_value":"IN","reason":"premise"}]}}