The principal part at of a function
is the portion of the Laurent series consisting of terms with negative degree. That is,
is the principal part of at . has an essential singularity at, if and only if the principal part is an infinite sum.
Famous quotes containing the words principal and/or part:
“The principal rule of art is to please and to move. All the other rules were created to achieve this first one.”
—Jean Racine (1639–1699)
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