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缺8數(12345679)[编辑 | 编辑源代码]
- 假如123456789 x 9 = 1111111111併不是非常有趣的。
- 事實上十進制中123456789 x 9 = 1111111101 , 偏偏有一位是0 。
- 奇怪在於去除了8 , 又得了12345679 x 9 = 111111111 。
- 123456789 x 9 + 9 = 1111111110
- 123456790 x 9 = 1111111110
- 12345679 x 9 = 111111111
- 12345678 x 9 + 9 = 111111111
- (12345678 + 1) x 9 = 111111111
- 12345679 x 9 = 111111111
缺8數的奇妙乘法性質[编辑 | 编辑源代码]
(缺8)
(缺7)
(缺5)
(缺4)
(缺2)
(缺1)
![{\displaystyle 12345679\times 1=12345679}](https://wikimedia.org/api/rest_v1/media/math/render/svg/7fe703c02269a4cd815585901b30b598811f264c)
![{\displaystyle 12345679\times 10=123456790}](https://wikimedia.org/api/rest_v1/media/math/render/svg/63abd20b3cc1d075efd997268e28bc5e8692964a)
![{\displaystyle 12345679\times 19=234567901}](https://wikimedia.org/api/rest_v1/media/math/render/svg/03a12624ee5a79455ff33fc48028723ddb1128c4)
![{\displaystyle 12345679\times 28=345679012}](https://wikimedia.org/api/rest_v1/media/math/render/svg/4e672e41b09234ec8b45eb3cede4a07c7db282da)
![{\displaystyle 12345679\times 37=456790123}](https://wikimedia.org/api/rest_v1/media/math/render/svg/a250b99b714df6ab9e8f2045e6ae69da3c903f8d)
![{\displaystyle 12345679\times 46=567901234}](https://wikimedia.org/api/rest_v1/media/math/render/svg/14ed6e883e43b24e383b319b82d4ed428d7b2df7)
![{\displaystyle 12345679\times 55=679012345}](https://wikimedia.org/api/rest_v1/media/math/render/svg/a80f3c3dea7c31b17d23dd2e818dec12746d2639)
![{\displaystyle 12345679\times 64=790123456}](https://wikimedia.org/api/rest_v1/media/math/render/svg/9d8e49f9dfe26bff412e017c9993db354b05741d)
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![{\displaystyle 12345679\times 2=24691358}](https://wikimedia.org/api/rest_v1/media/math/render/svg/1cd46e491c10cf61cda509fd515b8e42bb08bfc7)
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![{\displaystyle 12345679\times 38=469135802}](https://wikimedia.org/api/rest_v1/media/math/render/svg/9ce99fe82e10d3ccac4ea510e7edf50834f45d4b)
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![{\displaystyle 12345679\times 11=135802469}](https://wikimedia.org/api/rest_v1/media/math/render/svg/b0b83f0f6870c68fe29a14549f1e1a8b828bf2e8)
![{\displaystyle 12345679\times 29=358024691}](https://wikimedia.org/api/rest_v1/media/math/render/svg/6b9cf300ccdd9d0f8740ce0eb28f78af9267713c)
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![{\displaystyle 12345679\times 65=802469135}](https://wikimedia.org/api/rest_v1/media/math/render/svg/c0d38281ea827422b216f878b23c181e3fcf366f)
![{\displaystyle 12345679\times 4=49382716}](https://wikimedia.org/api/rest_v1/media/math/render/svg/2e6f23ee335290e44de3e764de4541bb3f1aac78)
![{\displaystyle 12345679\times 40=493827160}](https://wikimedia.org/api/rest_v1/media/math/render/svg/d64a3d7866c9bf7c2a0855da7603f910d691b172)
![{\displaystyle 12345679\times 76=938271604}](https://wikimedia.org/api/rest_v1/media/math/render/svg/4dd1598f933ff8d7e8f1572c76b82945f3ae9add)
![{\displaystyle 12345679\times 31=382716049}](https://wikimedia.org/api/rest_v1/media/math/render/svg/98f47fdbd3b1a6286df4e65f627288aa0475492c)
![{\displaystyle 12345679\times 67=827160493}](https://wikimedia.org/api/rest_v1/media/math/render/svg/760fd47846b5256042242093dc704b87864329bf)
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![{\displaystyle 12345679\times 5=61728395}](https://wikimedia.org/api/rest_v1/media/math/render/svg/44d964d8d9145477c7dd0e2f3b95249f84abf1b4)
![{\displaystyle 12345679\times 50=617283950}](https://wikimedia.org/api/rest_v1/media/math/render/svg/ff29f1e892826fbd7fdad38e37e2fd865de81789)
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![{\displaystyle 12345679\times 59=728395061}](https://wikimedia.org/api/rest_v1/media/math/render/svg/92a096361b82a9a42cba1706bdbe6863b0946a39)
![{\displaystyle 12345679\times 23=283950617}](https://wikimedia.org/api/rest_v1/media/math/render/svg/6214b098e23e8f2f9de989a4eb0ec172d8479487)
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![{\displaystyle 12345679\times 32=395061728}](https://wikimedia.org/api/rest_v1/media/math/render/svg/55931d9e5d5e22a0547601ba516dbf783f78ecfc)
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![{\displaystyle 12345679\times 41=506172839}](https://wikimedia.org/api/rest_v1/media/math/render/svg/975b06039fb8b5a40cb33dd5af388cef38fe0cbe)
![{\displaystyle 12345679\times 7=86419753}](https://wikimedia.org/api/rest_v1/media/math/render/svg/80a7fa933cc82f15d1daeed40a2503b291926043)
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![{\displaystyle 12345679\times 52=641975308}](https://wikimedia.org/api/rest_v1/media/math/render/svg/bcaf2bc650a96e5460d65f7afa0b417f77aba1c9)
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![{\displaystyle 12345679\times 16=197530864}](https://wikimedia.org/api/rest_v1/media/math/render/svg/903f7dee09112492ea3b5f8ce055948e31e1a4ae)
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![{\displaystyle 12345679\times 61=753086419}](https://wikimedia.org/api/rest_v1/media/math/render/svg/0a7e2033834a1b334863d94edae52f1327b9d82d)
![{\displaystyle 12345679\times 43=530864197}](https://wikimedia.org/api/rest_v1/media/math/render/svg/174942b09f8a731185eba6ae094006ef2d4dafe2)
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![{\displaystyle 12345679\times 8=98765432}](https://wikimedia.org/api/rest_v1/media/math/render/svg/d0244eafaf68ef66e1b821fb79304157c61f6723)
![{\displaystyle 12345679\times 80=987654320}](https://wikimedia.org/api/rest_v1/media/math/render/svg/991e1b47e15fa44f3fe2375a75856ec1022e754f)
![{\displaystyle 12345679\times 71=876543209}](https://wikimedia.org/api/rest_v1/media/math/render/svg/75f10f9bdc1a07392cae5d18414044a2e203006d)
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![{\displaystyle 12345679\times 3=37037037}](https://wikimedia.org/api/rest_v1/media/math/render/svg/be709a4f53e646b7631dd65111f96a7a58199aca)
![{\displaystyle 12345679\times 6=74074074}](https://wikimedia.org/api/rest_v1/media/math/render/svg/03cfe9855a0a657680697366d42c9eaa0f181a4c)
![{\displaystyle 12345679\times 9=111111111}](https://wikimedia.org/api/rest_v1/media/math/render/svg/a88b1e7001b76c87eeb2a94bc88da874542562c5)
![{\displaystyle 12345679\times 12=148148148}](https://wikimedia.org/api/rest_v1/media/math/render/svg/d2ebaced94c467eb08fd6d37e0d8422da4f230f0)
![{\displaystyle 12345679\times 15=185185185}](https://wikimedia.org/api/rest_v1/media/math/render/svg/b66f313fa7552bd25510d2b2de5da2564590debd)
![{\displaystyle 12345679\times 18=222222222}](https://wikimedia.org/api/rest_v1/media/math/render/svg/d9ef7368be0ba29e32a7aa4841196ff89c86effa)
![{\displaystyle 12345679\times 21=259259259}](https://wikimedia.org/api/rest_v1/media/math/render/svg/9e9248b857cbc750f4f91eb76e169875869401c4)
![{\displaystyle 12345679\times 24=296296296}](https://wikimedia.org/api/rest_v1/media/math/render/svg/41fc869723a6d3115b22d5689985777ab5ad32e7)
![{\displaystyle 12345679\times 27=333333333}](https://wikimedia.org/api/rest_v1/media/math/render/svg/d1ae4e238ad6af11f26e39c16c6167fc53cf7483)
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![{\displaystyle 12345679\times 33=407407407}](https://wikimedia.org/api/rest_v1/media/math/render/svg/0c1e4a8ec57c8f792f285d674711955f02e4980b)
![{\displaystyle 12345679\times 36=444444444}](https://wikimedia.org/api/rest_v1/media/math/render/svg/8fed5eae63c63796294b745dda0b5f9a3387cc92)
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![{\displaystyle 12345679\times 42=518518518}](https://wikimedia.org/api/rest_v1/media/math/render/svg/7d5769caefd1e87fcfb9e56d2e58232952d9b9cd)
![{\displaystyle 12345679\times 45=555555555}](https://wikimedia.org/api/rest_v1/media/math/render/svg/08c45ed04678e3a4f9f2be0b96941607d98a307f)
![{\displaystyle 12345679\times 48=592592592}](https://wikimedia.org/api/rest_v1/media/math/render/svg/0bb656d1a3a193c0341edc94e8242481f61dca35)
![{\displaystyle 12345679\times 51=629629629}](https://wikimedia.org/api/rest_v1/media/math/render/svg/337662cedef98024e2d044c247b6d900517abd7f)
![{\displaystyle 12345679\times 54=666666666}](https://wikimedia.org/api/rest_v1/media/math/render/svg/9d94c985ef443d2154d1b71e7514621c03dbdda0)
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![{\displaystyle 12345679\times 63=777777777}](https://wikimedia.org/api/rest_v1/media/math/render/svg/73726194765cf07fa0134964e1e8501f19f5afa4)
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![{\displaystyle 12345679\times 81=999999999}](https://wikimedia.org/api/rest_v1/media/math/render/svg/0e16e640824e29627cbcc6d8c4394dbaa1d720d7)
![{\displaystyle 12345679\times 9=111111111}](https://wikimedia.org/api/rest_v1/media/math/render/svg/a88b1e7001b76c87eeb2a94bc88da874542562c5)
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![{\displaystyle 12345679\times 999999999=12345678987654321}](https://wikimedia.org/api/rest_v1/media/math/render/svg/d35980b54500c56eb6c368112cb14e7606910829)
- 右邊是迴文數 , 左右兩邊對稱部份形成上升的金字塔 ; 中間重覆的數字下降 。
缺8數與循環小數1/81有關[编辑 | 编辑源代码]
![{\displaystyle {1 \over 81}=0.{\dot {0}}1234567{\dot {9}}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/6c10e1d45d810c59143095912501fc60235437da)
n/81的循環小數表示[编辑 | 编辑源代码]
![{\displaystyle {1 \over 81}=0.{\dot {0}}1234567{\dot {9}}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/6c10e1d45d810c59143095912501fc60235437da)
![{\displaystyle {3 \over 81}={1 \over 27}=0.{\dot {0}}3{\dot {7}}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/c759023e5509a15c38d7e2deca38a8c1de352029)
![{\displaystyle {9 \over 81}={1 \over 9}=0.{\dot {1}}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/f0d25e0cbd26d2cd4765e7d0e28808dd27ee8189)