Puiseux series
In mathematics, Puiseux series are a generalization of power series that allow for negative and fractional exponents of the indeterminate. For example, the series x − 2 + 2 x − 1 / 2 + x 1 / 3 + 2 x 11 / 6 + x 8 / 3 + x 5 + ⋯ = x − 12 / 6 + 2 x − 3 / 6 + x 2 / 6 + 2 x 11 / 6 + x 16 / 6 + x 30 / 6 + ⋯ {\displaystyle {\begin{aligned}x^{-2}&+2x^{-1/2}+x^{1/3}+2x^{11/6}+x^{8/3}+x^{5}+\cdots \\&=x^{-12/6}+2x^{-3/6}+x^{2/6}+2x^{11/6}+x^{16/6}+x^{30/6}+\cdots \end{aligned}}} is a Puiseux series in the indeterminate x.