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:
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—Tacitus (c. 55–c. 120)
“In the most worn, pedantic, introverted self-tormenter’s life, the greatest part is incalculable by him, unforeseen, unimaginable, and must be, until he can take himself up by his own ears. What am I? What has my will done to make me that I am? Nothing. I have been floated into this thought, this hour, this connection of events, by secret currents of might and mind, and my ingenuity and wilfulness have not thwarted, have not aided to an appreciable degree.”
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