Jacobsthal Trigonometric Functions

Apisit Pakapongpun (1), Natdanai Chailangka (2)
(1) Department of Mathematics, Faculty of Science, Burapha University, Thailand,
(2) Branch of Sciences and Mathematics, Faculty of Science and Technology, Rajamangala University of Technology Tawan-ok, Thailand

Abstract

Jacobsthal numbers satisfy a second order homogeneous recurrence relation $J_{n}=J_{n-1}+2J_{n-2}$ where $J_{n}$ denotes the $n^{th}$ Jacobsthal number. In this paper, the Jacobsthal sine, cosine, tangent and cotangent are defined, and some identities of Jacobsthal trigonometric functions are provided.

Full text article

Generated from XML file

References

D. Kalman and R. Mena, “The fibonacci numbers-exposed,” The Mathematical Magazine, vol. 76, no. 3, pp. 167–181, 2003. https://doi.org/10.2307/3219318.

T. Koshy, Fibonacci and Lucas numbers with applications. New York: Wiley-Interscience, 2001. https://doi.org/10.1002/9781118033067.

A. F. Horadam, “Jacobsthal representation numbers,” The Fibonacci Quarterly, vol. 34, pp. 40–54, 1996. https://doi.org/10.1080/00150517.1996.12429096.

R. M. Smith, “Introduction to analytic fibonometry,” Alabama Journal of Mathematics, vol. 25, no. 2, pp. 27–36, 2001.

V. Srimuk and A. Pakapongpun, “Identities of k-fibonometric functions,” Burapha Science Journal, vol. 25, no. 3, pp. 880–891, 2020.

W. M. Abd-Elhameed, O. M. Alqubori, and A. K. Amin, “New results for certain jacobsthal-type polynomials,” Mathematics, vol. 13, no. 5, p. 715, 2025. https://doi.org/10.3390/math13050715.

I. Ye¸silyurt and N. De˘girmen, “Non-newtonian jacobsthal and jacobsthal-lucas numbers: A new look,” Filomat, vol. 39, no. 4, pp. 1093–1109, 2025. https://doi.org/10.2298/FIL2504093Y

Authors

Apisit Pakapongpun
Natdanai Chailangka
natdanai_ch@rmutto.ac.th (Primary Contact)
Pakapongpun, A., & Chailangka, N. (2025). Jacobsthal Trigonometric Functions. Journal of the Indonesian Mathematical Society, 31(4), 1808. https://doi.org/10.22342/jims.v31i4.1808

Article Details

Crossref
Scopus
Google Scholar
Europe PMC