$\epsilon$

10^-1

10^-2

10^-3

10^-4

$\cdots$

$N=\left[\frac{1}{\epsilon }\right]$

$10,11,\cdots$

${10}^2,{10}^2+1,\cdots$

${10}^3,{10}^3+1,\cdots$

${10}^4,{10}^4+1,\cdots$

$\cdots$

$d=\left|a_n-a\right|$

$d<{10}^{-1}$

$d<{10}^{-2}$

$d<{10}^{-3}$

$d<{10}^{-4}$

$\cdots$