Skip to content

Learn

Number Theory

Level 2 / foundation

Primes (<= 50)

3 visual steps / prime trial tests

1. Limit tests

prime? 471. Limit testsOnly test primes up to sqrt.1sqrt(47) is under 72test 2, 3, 5347 is prime
Only test primes up to sqrt.

Only test primes up to sqrt.

2. Try primes

prime? 472. Try primesCheck the small prime divisors.1sqrt(47) is under 72test 2, 3, 5347 is prime
Check the small prime divisors.

Check the small prime divisors.

3. Decide

prime? 473. DecideStop when every test fails.1sqrt(47) is under 72test 2, 3, 5347 is prime
Stop when every test fails.

Stop when every test fails.

Practice Level 2

Use the visible move, then type only when the answer is clear.

Start Level