Formal derivative of a formal power series

• formal power series Define the formal derivative of F as follows

• $F={\sum }_{n=0}^{\infty }{f}_n{x}^n$

• $F^{\prime }={\sum }_{n=1}^{\infty }n{f}_n{x}^{n-1}={\sum }_{n=0}^{\infty }(n+1)f_{n+1}{x}^n$

• Leibniz rule $(FG{)}^{\prime }=F^{\prime }G+F{G}^{\prime }$ etc.

[Polynomials and Formal Power Series (3) Linear Asymptotes and Formal Power Series | maspy’s HP https://maspypy.com/%e5%a4%9a%e9%a0%85%e5%bc%8f%e3%83%bb%e5%bd%a2%e5%bc%8f%e7%9a%84%e3%81%b9% e3%81%8d%e7%b4%9a%e6%95%b0%ef%bc%88%ef%bc%93%ef%bc%89%e7%b7%9a%e5%bd%a2%e6%bc%b8%e5%8c%96%e5%bc%8f%e3%81%a8%e5%bd%a2%e5%bc%8f]

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