#UnionCTF #!/usr/bin/env python3 from secrets import flag, musical_key from Crypto.Util.number import isPrime import math def sieve_for_primes_to(n): # Copyright Eratosthenes, 204 BC size = n//2 sieve = [1]*size limit = int(n**0.5) for i in range(1, limit): if sieve[i]: val = 2*i+1 tmp = ((size-1) -…