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arXiv · 1101.0526

Hadamard grade of power series

J. -P. Allouche·M. Mendès France
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Abstract

The Hadamard product of two power series $\sum a_n z^n$ and $\sum b_n z^n$ is the power series $\sum a_n b_n z^n$. We define the (Hadamard) grade of a power series $A$ to be the least number (finite or infinite) of algebraic power series, the Hadamard product of which equals $A$. We study and discuss this notion.

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J. -P. Allouche, M. Mendès France. 2011-03-25. Hadamard grade of power series. https://arxiv.org/abs/1101.0526

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