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The k-Generalized Lucas Numbers Close to a Power of 2

  • Abdullah Açikel , Nurettin Irmak EMAIL logo and László Szalay
Published/Copyright: August 4, 2023
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ABSTRACT

Let k ≥ 2 be a fixed integer. The k-generalized Lucas sequence { Ln(k) }n0 starts with the positive integer initial values k, 1, 3, …, 2 k−1 – 1, and each term afterward is the sum of the k consecutive preceding elements. An integer n is said to be close to a positive integer m if n satisfies | nm |<m . In this paper, we combine these two concepts. We solve completely the diophantine inequality

| Ln(k)2m |<2m/2

in the non-negative integers k, n, and m. This problem is equivalent to the resolution of the equation Ln(k)=2m+t with the condition |t| < 2 m/2, t . We also discovered a new formula for Ln(k) which was very useful in the investigation of one particular case of the problem.

2020 Mathematics Subject Classification: 11J86; 11B39

(Communicated by István Gaál)


Funding statement: For L. Szalay, the research was supported in part by National Research, Development and Innovation Office Grant 2019-2.1.11-TÉT-2020-00165, by Hungarian National Foundation for Scientific Research Grant No. 128088 and No. 130909, and by the Slovak Scientific Grant Agency VEGA 1/0776/21.

Acknowledgement

We are grateful the referee for calling our attention to an extension possibility of the former problem by considering the notion of closeness. We thank also V. Csanady for fitting the saturation curve.

REFERENCES

[1] AÇIKEL, A.—AMROUCHE, S.—BELBACHIR, H.—IRMAK, N.: On k-generalized Lucas sequence with its triangle, submitted.Search in Google Scholar

[2] BELBACHIR, H.—KOMATSU, T.—SZALAY, L.: Linear recurrences associated to rays in Pascal’s triangle and combinatorial identities, Math. Slovaca 64(2) (2014), 1–1410.2478/s12175-014-0203-0Search in Google Scholar

[3] BELBACHIR, H.—SZALAY, L.: On the arithmetic triangles, Šiauliai Math. Seminar 9(17) (2014), 15–26Search in Google Scholar

[4] MARQUES, D.: k-generalized Fibonacci numbers with only one distinct digit, Util. Math. 98 (2015), 23–31Search in Google Scholar

[5] BRAVO, J. J.—LUCA, F.: Powers of two in generalized Fibonacci sequences, Rev. Colombiana Mat. 46(1) (2012), 67–79Search in Google Scholar

[6] BRAVO, J. J.—GÓMEZ, C.A.— HERRERA, J.L.: k-Fibonacci numbers close to a power of 2, Quaest. Math. 44(12) (2021), 1681–169010.2989/16073606.2020.1818645Search in Google Scholar

[7] CHERN, S.—CUI, A.: Fibonacci numbers close to a power of 2, Fibonacci Quart. 52(4) (2014), 344–34810.1080/00150517.2014.12427883Search in Google Scholar

[8] COHEN, H.: Number Theory I: Tools and Diophantine Equations. Grad. Texts in Math. 239, Springer, 2007.Search in Google Scholar

[9] DRESDEN, G.—WANG, Y.: Sums and convolutions of k-Bonacci and k-Lucas numbers, Integers 21 (2021), Art. ID A56.Search in Google Scholar

[10] SANCHEZ, S.G.—LUCA, F.: Linear combinations of factorials and S-units in a binary recurrences sequence, Ann. Math. Québec 38 (2014), 169–18810.1007/s40316-014-0025-zSearch in Google Scholar

[11] LUCA, F.—SZALAY, L.: Fibonacci numbers of the form pa ± pb + 1, Fibonacci Quart. 45(2) (2007), 98–10310.1080/00150517.2007.12428223Search in Google Scholar

[12] MATVEEV, E. M.: An explicit lower bound for a homogeneous rational linear form in the logarithms of algebraic numbers, Izv. Math. 64 (2000), 1217–126910.1070/IM2000v064n06ABEH000314Search in Google Scholar

[13] WOLFRAM, D.A: Solving generalized Fibonacci recurrences, Fibonacci Quart. 36(2) (1998), 129–14510.1080/00150517.1998.12428948Search in Google Scholar

[14] YILMAZ, N.—TASKARA, N.: Tribonacci and Tribonacci-Lucas numbers via the determinants of special matrices, Appl. Math. Sci. 8(39) (2014), 1947–195510.12988/ams.2014.4270Search in Google Scholar

Received: 2021-09-16
Accepted: 2022-11-01
Published Online: 2023-08-04

© 2023 Mathematical Institute Slovak Academy of Sciences

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