Sandbox2

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<R>1:8</R> <M>1:8</M>

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$\operatorname {erfc} (a)={\frac {2}{\sqrt {\pi }}}\int _{x}^{\infty }e^{-t^{2}}\,dt={\frac {e^{-x^{2}}}{x{\sqrt {\pi }}}}\sum _{n=0}^{\infty }(-1)^{n}{\frac {(2n)!}{n!(2x)^{2n}}}$

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select
  *
from
  dual
;