{"id":"is-prime-trial-division-bound","text":"`is_prime` in prime-arrangements checks divisors only up to `int(k**0.5) + 1`, making it O(sqrt(k)) per call — sufficient for the n<=100 constraint but would need a sieve for larger inputs.","truth_value":"IN","source":"entries/2026/06/06/prime-arrangements-solution.md","source_url":"","source_hash":"","justifications":[],"dependents":[],"metadata":{},"created_at":"","updated_at":"","reviewed_at":"","verified_at":"","retracted_at":"","explanation":{"steps":[{"node":"is-prime-trial-division-bound","truth_value":"IN","reason":"premise"}]}}