エラトステネスの篩
https://rconv.ongaeshi.me/?q=MQAgFgLhAODOBcB6RBHAlmiBDAdAYwHsBbRWMNALwFcitFMBTI2RLADgCMBWBgJg968A7AAZOAFgDMvAIwA2ACbiAUAoYAzEHjAM8AawD60AE5oiDABQA7GgEplILVlgMQNog5AB3HVZAyQCF9PR3UsABsXTx8GP15A4MdHCGMqBk8GSPSkkAteHBxrGgBaGVtbHAYsbRAFAhAAHzQrNQAPBpCktE13EABSEGa2kABeEZARTpzjBggqYz8wrKmQWIVOtc6ZuYXA1OzVluVN5QAlQisANxwXCAsITHCGeBAAIkAKhkBLhkAJhkBOhkAxhkAswy-QB2DIBL71eABpahosFRwhAXjICjIRLZavUGgwOo5jKMQABtAC6GUq1TAGMa7hxSTxAB46W4aINNNpdIYTGZLO57I5NricAArAjNCxQt72TZAA