Erfc[z] \[Proportional] Erfc[Subscript[z, 0]] - (2/(E^Subscript[z, 0]^2 Sqrt[Pi])) (z - Subscript[z, 0]) + ((2 Subscript[z, 0])/(E^Subscript[z, 0]^2 Sqrt[Pi])) (z - Subscript[z, 0])^2 + \[Ellipsis] /; (z -> Subscript[z, 0])

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2007-05-02