求一组大于7的三个连续连续自然数分别能被7,8,9整除
问题描述:
求一组大于7的三个连续连续自然数分别能被7,8,9整除
答
511=73*7
512=8*64
513=9*57
...
8(63n+1) - 1 = 8*7*9n +7 = 7(72n+1)
8(63n+1)=8(63n+1)
8(63n+1) + 1 = 8*7*9n+ 9 = 9(56n+1),
n=0,1,2,...