$ c i + b k + a k i + a k i $ {\displaystyle \$c^{i}+b_{k}+a_{k}^{i}+a_{k}^{i}\$}
1 σ 2 π exp ( − ( x − μ ) 2 2 σ 2 ) {\displaystyle {\frac {1}{\sigma {\sqrt {2\pi }}}}\exp \left(-{\frac {(x-\mu )^{2}}{2\sigma ^{2}}}\right)}
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