缺8數
缺8數(12345679)
編輯為什麼會少了個8
編輯- 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
缺8數的奇妙乘法性質
編輯數字輪流休息(一)
編輯12345679 x 1 = 12345679 (缺8)
12345679 x 2 = 24691358 (缺7)
12345679 x 4 = 49382716 (缺5)
12345679 x 5 = 61728395 (缺4)
12345679 x 7 = 86419753 (缺2)
12345679 x 8 = 98765432 (缺1)
數字輪流休息(二)
編輯缺8
編輯12345679 x 1 = 12345679
12345679 x 10 = 123456790
12345679 x 19 = 234567901
12345679 x 28 = 345679012
12345679 x 37 = 456790123
12345679 x 46 = 567901234
12345679 x 55 = 679012345
12345679 x 64 = 790123456
12345679 x 73 = 901234567
缺7
編輯12345679 x 2 = 24691358
12345679 x 11 = 135802469
12345679 x 20 = 246913580
12345679 x 29 = 358024691
12345679 x 38 = 469135802
12345679 x 47 = 580246913
12345679 x 56 = 691358024
12345679 x 65 = 802469135
12345679 x 74 = 913580246
缺5
編輯12345679 x 4 = 49382716
12345679 x 13 = 160493827
12345679 x 22 = 271604938
12345679 x 31 = 382716049
12345679 x 40 = 493827160
12345679 x 49 = 604938271
12345679 x 58 = 716049382
12345679 x 67 = 827160493
12345679 x 76 = 938271604
缺4
編輯12345679 x 5 = 61728395
12345679 x 14 = 172839506
12345679 x 23 = 283950617
12345679 x 32 = 395061728
12345679 x 41 = 506172839
12345679 x 50 = 617283950
12345679 x 59 = 728395061
12345679 x 68 = 839506172
12345679 x 77 = 950617283
缺2
編輯12345679 x 7 = 86419753
12345679 x 16 = 197530864
12345679 x 25 = 308641975
12345679 x 34 = 419753086
12345679 x 43 = 530864197
12345679 x 52 = 641975308
12345679 x 61 = 753086419
12345679 x 70 = 864197530
12345679 x 79 = 975308641
缺1
編輯12345679 x 8 = 98765432
12345679 x 17 = 209876543
12345679 x 26 = 320987654
12345679 x 35 = 432098765
12345679 x 44 = 543209876
12345679 x 53 = 654320987
12345679 x 62 = 765432098
12345679 x 71 = 876543209
12345679 x 80 = 987654320
三位數重覆三次
編輯12345679 x 3 = 37037037
12345679 x 6 = 74074074
12345679 x 9 = 111111111
12345679 x 12 = 148148148
12345679 x 15 = 185185185
12345679 x 18 = 222222222
12345679 x 21 = 259259259
12345679 x 24 = 296296296
12345679 x 27 = 333333333
12345679 x 30 = 370370370
12345679 x 33 = 407407407
12345679 x 36 = 444444444
12345679 x 39 = 481481481
12345679 x 42 = 518518518
12345679 x 45 = 555555555
12345679 x 48 = 592592592
12345679 x 51 = 629629629
12345679 x 54 = 666666666
12345679 x 57 = 703703703
12345679 x 60 = 740740740
12345679 x 63 = 777777777
12345679 x 66 = 814814814
12345679 x 69 = 851851851
12345679 x 72 = 888888888
12345679 x 75 = 925925925
12345679 x 78 = 962962962
12345679 x 81 = 999999999
純位數
編輯12345679 x 9 = 111111111
12345679 x 18 = 222222222
12345679 x 27 = 333333333
12345679 x 36 = 444444444
12345679 x 45 = 555555555
12345679 x 54 = 666666666
12345679 x 63 = 777777777
12345679 x 72 = 888888888
12345679 x 81 = 999999999
階梯上升的金字塔
編輯12345679 x 9 = 111111111
12345679 x 99 = 1222222221
12345679 x 999 = 12333333321
12345679 x 9999 = 123444444321
12345679 x 99999 = 1234555554321
12345679 x 999999 = 12345666654321
12345679 x 9999999 = 123456777654321
12345679 x 99999999 = 1234567887654321
12345679 x 999999999 = 12345678987654321
- 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
編輯1/81 = 0.(012345679)
- 1/81循環節九位數字012345679。
n/81的循環小數表示
編輯1/81 = 0.(012345679)
3/81 = 0.(037)
9/81 = 0.(1)
27/81 = 0.(3)