Sandbox

<R>1:20</R>

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

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hola [1]

1. Shaner NC, Campbell RE, Steinbach PA, Giepmans BN, Palmer AE, and Tsien RY. Improved monomeric red, orange and yellow fluorescent proteins derived from Discosoma sp. red fluorescent protein. Nat Biotechnol. 2004 Dec;22(12):1567-72. DOI:10.1038/nbt1037 |
2. Ubhayasekera W, Muñoz IG, Vasella A, Ståhlberg J, and Mowbray SL. Structures of Phanerochaete chrysosporium Cel7D in complex with product and inhibitors. FEBS J. 2005 Apr;272(8):1952-64. DOI:10.1111/j.1742-4658.2005.04625.x |

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select
  *
from
  dual
;

x < 1:20

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això és una prova tonta