b****d 发帖数: 1311 | 1 Suppose q = (x,715), let t = 715/q, then
x^61 - x = x ( x^60 - 1 )
q | x , & (x, t) = 1 ==> t | ( x^60 - 1 )
QED | u**x 发帖数: 45 | 2
By Fermat's,
x^5=x mod 5, -> x^61=(x^5)^10*x=x mod 5
x^11=x mod 11 -> x^61=(x^11)^5*x^6=x mod 11
x^13=x mod 13 -> x^61=(x^13)^4*x^9=x mod 13
Thus x^61=x (mod 715) |
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