Tribonacci numbers as sum or difference of powers of 2

Year 2025, Volume: 21 Issue: 2, 147 - 151, 27.06.2025

Fatih Erduvan

https://doi.org/10.18466/cbayarfbe.1528991

Abstract

This paper investigates Tribonacci numbers can be expressed as either the sum or difference of two distinct powers of 2. Namely, we address the problem of expressing Tribonacci numbers in the form

T_n=2^x±2^y

in positive integers with 1≤y≤x. Our findings reveal specific instances where such representations are possible, including examples like the seventh Tribonacci number expressed both as the sum and the difference of powers of 2. Additionally, we identify Tribonacci numbers that can be represented as the differences of Mersenne numbers, specifically, the numbers 2, 4, 24, and 504. These results enhance the understanding of the structural properties of Tribonacci sequences and their relationships with exponential and Mersenne-based number systems.

Keywords

Diophantine equations , Tribonacci numbers , Baker’s Theory

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