证明：70!,61!对模71同余
问题描述：
证明：70!,61!对模71同余
答
70!-61!=70*69*68*67*66*65*64*63*62*61!-61!=(70*69*68*67*66*65*64*63*62-1) *61!因为 70*69*68*67*66*65*64*63*62 mod 71=(71-1)(71-2)(71-3)(71-4)(71-5)(71-6)(71-7)(71-8)(71-9) mod 71= -9!mod 71= -7!(8*9) ...