※ [本文轉錄自 Gandalf 看板]
142857 is a cyclic number
its digits always appear in the same order
but will rotate around when multiplied by any number from1 to 6:
142857 x 1 = 142857
142857 x 2 = 285714
142857 x 3 = 428571
142857 x 4 = 571428
142857 x 5 = 714285
142857 x 6 = 857142
Pretty cool,huh?
Now multiply 142857 by 7.
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