Answers with the working exposed.

Prime Number Lab is an independent educational tool for checking primality, decomposing composite integers, listing divisors, locating neighboring primes, and generating primes within a bounded range.

Algorithms

Single-number analysis uses optimized trial division through the square root, checking 2 and 3 before candidates of the form 6k±1. Range generation uses the Sieve of Eratosthenes. The one-number limit is 10¹²; ranges end at 10⁶ and span at most 100,000 integers.

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