**Volume 24** ▶ Number 1 ▷ Number 2 ▷ Number 3 ▷ Number 4

**Happy φ(164)-th birthday, Prof. Tony Shannon!**

*Editorial. Pages 1—2*

Krassimir T. Atanassov and József Sándor

Editorial (PDF, 250 Kb)

**On a new arithmetic function**

*Original research paper. Pages 3—10*

Krassimir T. Atanassov and József Sándor

Full paper (PDF, 177 Kb) | Abstract

**An identical equation for arithmetic functions of several variables and applications**

*Original research paper. Pages 11—17*

Vichian Laohakosol and Pinthira Tangsupphathawat

Full paper (PDF, 180 Kb) | Abstract

**Revisiting some old results on odd perfect numbers**

*Original research paper. Pages 18—25*

Jose Arnaldo Bebita Dris and Doli-Jane Uvales Tejada

Full paper (PDF, 177 Kb) | Abstract

**The Redheffer numbers and their applications**

*Original research paper. Pages 26—37*

Ömür Deveci and Anthony G. Shannon

Full paper (PDF, 142 Kb) | Abstract

**Results on generalized negabent functions**

*Original research paper. Pages 38—44*

Rashmeet Kaur and Deepmala Sharma

Full paper (PDF, 166 Kb) | Abstract

**A new symmetric endomorphism operator for some generalizations of certain generating functions**

*Original research paper. Pages 45—58*

Ali Boussayoud, Abdelhamid Abderrezzak and Serkan Araci

Full paper (PDF, 207 Kb) | Abstract

**Simple applications of continued fractions and an elementary result on Heron’s algorithm**

*Original research paper. Pages 59—69*

Antonino Leonardis

Full paper (PDF, 904 Kb) | Abstract

**Generalized dual Fibonacci quaternions with dual coefficient**

*Original research paper. Pages 70—85*

Fügen Torunbalcı Aydın

Full paper (PDF, 226 Kb) | Abstract

**The structure of prime sums**

*Original research paper. Pages 86—91*

J. V. Leyendekkers and A. G. Shannon

Full paper (PDF, 114 Kb) | Abstract

**Some combinatorial identities via Stirling transform**

*Original research paper. Pages 92—98*

Fouad Bounebirat, Diffalah Laissaoui and Mourad Rahmani

Full paper (PDF, 191 Kb) | Abstract

**Explicit expression for symmetric identities of w-Catalan–Daehee polynomials**

*Original research paper. Pages 99—111*

Taekyun Kim, Seog-Hoon Rim, Dmitry V. Dolgy and Sung-Soo Pyo

Full paper (PDF, 209 Kb) | Abstract

**On the Diophantine equation L_{n} − L_{m} = 3 • 2^{a}**

*Original research paper. Pages 112—119*

Zafer Şiar and Refik Keskin

Full paper (PDF, 191 Kb) | Abstract

**On the convergence of second-order recurrence series**

*Original research paper. Pages 120—127*

Bijan Kumar Patel and Prasanta Kumar Ray

Full paper (PDF, 150 Kb) | Abstract

**Valuations, arithmetic progressions, and prime numbers**

*Original research paper. Pages 128—132*

Shin-ichiro Seki

Full paper (PDF, 156 Kb) | Abstract

**Canonical matrices with entries integers modulo p**

*Original research paper. Pages 133—143*

Krasimir Yordzhev

Full paper (PDF, 173 Kb) | Abstract

**Extremal chemical trees of the first reverse Zagreb beta index**

*Original research paper. Pages 144—148*

Süleyman Ediz and Mesut Semiz

Full paper (PDF, 133 Kb) | Abstract

**Editorial note**

*Pages 149—150*

Editorial (PDF, 35 Kb)

*This issue of the International Journal “Notes on Number Theory and Discrete Mathematics” is published with the financial support of the Bulgarian National Science Fund, Grant Ref. No. DNP-06-38/2017.*