Integer which is Multiplied by 9 when moving Last Digit to First/Proof 2
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Theorem
Let $N$ be the positive integer:
- $N = 10 \, 112 \, 359 \, 550 \, 561 \, 797 \, 752 \, 808 \, 988 \, 764 \, 044 \, 943 \, 820 \, 224 \, 719$
$N$ is the smallest positive integer $N$ such that if you move the last digit to the front, the result is the positive integer $9 N$.
Proof
From Integer which is Multiplied by Last Digit when moving Last Digit to First, $N$ is equal to the recurring part of the fraction:
- $q = \dfrac {a_1} {10 a_1 - 1}$
where $a_1 = 9$.
Thus:
- $q = \dfrac 9 {10 \times 9 - 1} = \dfrac 9 {89}$
Hence:
Decimal Expansion
- $\dfrac 9 {89} = 0 \cdotp \dot 10112 \, 35955 \, 05617 \, 97752 \, 80898 \, 87640 \, 44943 \, 82022 \, 471 \dot 9$
$\Box$
The result follows.
$\blacksquare$