Period of Reciprocal of 729 is 81/Mistake

Source Work

1986: David Wells: Curious and Interesting Numbers:

The Dictionary

$729$

1997: David Wells: Curious and Interesting Numbers (2nd ed.):

The Dictionary

$729$

Mistake

$1 / 729$ has a decimal period of $81$ digits, which can be arranged in groups of $9$ digits, reading across each row, in this pattern:

$\ds 001 \, 371 \, 742$

$\ds $

$\ds 112 \, 482 \, 853$

$\ds $

$\ds 223 \, 593 \, 964$

$\ds $

$\ds 334 \, 705 \, 075$

$\ds $

$\ds 445 \, 816 \, 186$

$\ds $

$\ds 556 \, 927 \, 297$

$\ds $

$\ds 668 \, \color {red} 6 38 \, 408$

$\ds $

$\ds 779 \, 149 \, 519$

$\ds $

$\ds 890 \, 260 \, 631$

$\ds $

The $\color { red } {\text {red} }$ digit is wrong.

Instead of $6$ it should be $0$:

$\ds 001 \, 371 \, 742$

$\ds $

$\ds 112 \, 482 \, 853$

$\ds $

$\ds 223 \, 593 \, 964$

$\ds $

$\ds 334 \, 705 \, 075$

$\ds $

$\ds 445 \, 816 \, 186$

$\ds $

$\ds 556 \, 927 \, 297$

$\ds $

$\ds 668 \, \color {red} 0 38 \, 408$

$\ds $

$\ds 779 \, 149 \, 519$

$\ds $

$\ds 890 \, 260 \, 631$

$\ds $

Sources

1986: David Wells: Curious and Interesting Numbers ... (previous) ... (next): $729$
1997: David Wells: Curious and Interesting Numbers (2nd ed.) ... (previous) ... (next): $729$