Regular part explained

In mathematics, the regular part of a Laurent series consists of the series of terms with positive powers.^[1] That is, if

f(z) = \sum ^{inf ty} _{n =-inf ty} a _{n} (z - c) ^{n,} then the regular part of this Laurent series is\sum ^{inf ty} _{n =0} a _{n} (z - c) ^{n.}

In contrast, the series of terms with negative powers is the principal part.^[1]

Notes and References

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