This paper is devoted to study the almost convergent sequence space $$\widehat{c}(\varPhi )$$ derived by the Euler totient matrix. It is proved that the space $$\widehat{c}(\varPhi )$$ and the space of all almost convergent sequences are linearly isomorphic. Further, the $$\beta $$-dual of the space $$\widehat{c}(\varPhi )$$ is determined and Euler totient core of a complex-valued sequence has been defined. Finally, inclusion theorems related to this new type of core are obtained.

中文翻译：

---

几乎收敛和欧拉托特矩阵

本文致力于研究由欧拉托特矩阵导出的几乎收敛的序列空间$$\widehat{c}(\varPhi )$$。证明了空间$$\widehat{c}(\varPhi )$$与所有几乎收敛序列的空间是线性同构的。此外，确定了空间 $$\widehat{c}(\varPhi )$$ 的 $$\beta $$-dual 并定义了复值序列的 Euler totient 核心。最后，得到与这种新型核相关的包含定理。