$(p,q)^{th}$ $\psi-$order and $(p,q)^{th}$ $\psi-$type of Entire and Meromorphic Functions and Some of its Estimation

# Dibyendu Banerjee^{1} and Simul Sarkar^{2}

^{1}Department of Mathematics, Visva-Bharati, Santiniketan, West Bengal, India.

^{2}Shikarpur High School (H.S), Mathabhanga, West Bengal, India.**Abstract:** We introduce the concept of $(p,q)^{th}$ $\psi-order$ and $(p,q)^{th}$ $\psi-type$ of entire and meromorphic functions to generalise some results related to the $\varphi-order$ concept introduced by Chyzhykov-Semochko in [7]. In this paper we establish some estimates of the sum, product and the derivative of entire and meromorphic functions in the complex plane.

**Keywords:** Entire function, Meromorphic function, $(p,q)^{th}$ $\psi-order$, $(p,q)^{th}$ $\psi-type$.

**Cite this article as:** Dibyendu Banerjee and Simul Sarkar, *$(p,q)^{th}$ $\psi-$order and $(p,q)^{th}$ $\psi-$type of Entire and Meromorphic Functions and Some of its Estimation*, Int. J. Math. And Appl., vol. 9, no. 3, 2021, pp. 19-31.

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