关于《孙子定理》的看法:孙子定理

  学过初等数论的人都知道:里边有一个《孙子定理》,求未知数要用到大衍求一术,但我觉得这样做太麻烦,而我有更好的方法:  比如:某数除以59余26,除以73余42,除以89余34,除以97余13,除以101余3,求最小的某数.
  (若用大衍求一术,至少用1小时(手算),我用15分可求出).
  解 根据题意(满足后面两条件)得:101x + 3 = 97y + 13,
  即101x = 97y + 10(不定方程),
  97y = 101x - 10,
  97y = 97x + (4x - 10).
  设t = ■,97t = 4x - 10,
  4x = 97t + 10 = 96t + 8 + (t + 2),取t = 2,则x = 51.
  101 × 51 + 3 = 5154,5154是满足除以97余13和除以101余3的最小正整数.
  增加第三个条件,即:
  89x + 34 = (97 × 101)y + 5154,
  即89x = 97 × 101y + 5120 89x = (110 × 89)y + 7y + 57 × 89 + 47.
  设t = ■,89t = 7y + 47,7y = 89t - 47 = 84t - 49 + 5t + 2.
  取t = 1,则y = 6.
  6 × 97 × 101 + 5154 = 63936是满足后3个条件的最小正整数.
  同理:73x + 42 = (89 × 97 × 101)y + 63936,
  73x = 89 × 97 × 101y + 63894,
  即73x = 11944 × 73y + 21y + 875 × 73 + 19.
  设t = ■,21y = 73t - 19 = 63t + 10t - 19,取t = 4,y = 13.
  则89 × 97 × 101 × 13 + 63936 = 11399065是满足后4个条件的最小数.
  最后一个条件:
  59x + 26 = (73 × 89 × 97 × 10)1y + 11399065,
  即59x = 73 × 89 × 97 × 101y + 11399039,
  59x = 1078832 × 59y + 21y + 193204 + 3,
  即59t = 21y + 3 21y = 59t - 3,
  21y = 42t + 17t - 3,21s = 17t - 3,17t = 17s + 4s + 3,取17v = 4s + 3,取s = 12,t = 15,y = 42,则73 × 89 × 97 × 101 × 42 + 11399065 = 2684745643.这是此题的最小解.

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