Prime numbers start with even numbers, remember 2, 3, 5, 7(2, 3, 5, 7). Don't worry, you can make them into jingles. If the number of digits is 4 and 1, then the number of digits is 1, 3,7 (41,43,47,1,13, 17), if Unit 1, 7 is as follows (3 1, 37,61,67). If the ten digits are occupied by 7, the unit level is 1, 9,3 (71,79,73)19. ( 19、97)。

The prime number table within 100 is Dingdang II.

Two, three, five, seven, eleven, thirteen, seventeen, nineteen, two three nine, three one seven. Keep in mind that 539, 6 17, 4 137, 7 139, 83, 89, 97, 2, 3, 5, 7, 1 3, 7, 9 is more than a dozen, 2, 5.

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The prime number table within 100 is Dingdang III.

2357 1 1， 13 17 19，23293 1 1，374 14 13，47535 19，6 1677 1 1， 73798 13 and 8997, 2, 3, 5, 7 and 1 1, followed by 17, 9.

43,47,53, (43,47,53), 59,61,67, (59,61,67), 71,73,79, (7/kloc-0.