= Picard theorem
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The <Picard theorem> has two forms concerning the <image> of a <holomorphic function>. The <Little Picard theorem> permits at most one <omitted value> for a nonconstant <entire function>. The <Great Picard theorem> is local: near an isolated <essential singularity>, every complex value except possibly one occurs infinitely often. The <complex exponential function> $e^z$ and the <function> $e^{1/z}$ show that the possible exception is necessary.
Émile Picard presented the research in 1879 and published proofs in his 1880 memoir. Its opening footnote lists communications to the Académie des Sciences on 28 April, 19 May, and 20 October 1879; sections 3 and 15 contain the global and local results respectively. https://numdam.org/articles/10.24033/asens.187/[Picard, Mémoire sur les fonctions entières (1880), pp. 145, 147-148, 164-166]{ref}
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