• P-ISSN 0974-6846 E-ISSN 0974-5645

Indian Journal of Science and Technology

Article

Indian Journal of Science and Technology

Year: 2022, Volume: 15, Issue: 35, Pages: 1683-1690

Original Article

On Bounds of Non-Deficient Numbers

Received Date:05 March 2022, Accepted Date:11 July 2022, Published Date:03 September 2022

Abstract

Objectives: To improve the upper bounds of a quasi perfect number and give an important result on its divisibility with primes. Methods: A positive integer n is quasi perfect if s (n) >2n + 1, where s (n) denotes the sum of the positive divisors of n. However, the existence of a quasi perfect number, which is a Non-Deficient number, is still an open problem. We use R(n), the sum of the reciprocals of distinct primes dividing the quasi perfect number, to derive lemmas and improve the bounds obtained by earlier authors. Findings: We improve the upper bounds for R(n), when n is quasi perfect with gcd (15, n) = 3 or gcd (15, n) = 5. As a consequence, we establish that a quasi perfect number, if exists, is divisible by both 3 and 5 or by none of them. Novelty: The unique method of using R(n) also resulted in finding an important result that 3, 5 and 7 cannot divide any quasi perfect number. Mathematics Subject Classification: 11A05, 11A25.

Keywords: non-deficient number; quasi perfect number; sum of the divisor; sum of the reciprocal; bounds of perfect number; number of divisors

References

  1. Abbott HL, Aull CE, Brown E, Suryanarayana D. Quasiperfect numbers. Acta Arithmetica. 1973;22(4):439–447. Available from: https://doi.org/10.4064/aa-22-4-439-447
  2. Abbott H, Aull C, Brown E, Suryanarayana D. Corrections to the paper "Quasiperfect numbers" Acta Arithmetica. 1976;29(4):427–428. Available from: https://doi.org/10.4064/aa-29-4-427-428
  3. Kishore M. Odd integers N with five distinct prime factors for which 2−10−12 < σ(N)/N < 2 +10−12. Mathematics of Computation, American Mathematical Society. 1978;32:303–309. Available from: https://doi.org/10.1090/S0025-5718-1978-0485658-X
  4. Kishore M. On odd perfect, quasiperfect, and odd almost perfect numbers. Mathematics of Computation. 1981;36(154):583–586. Available from: https://doi.org/10.1090/S0025-5718-1981-0606516-3
  5. Cohen GL. The non-existence of quasi perfect numbers of certain form. Fibonacci Quaterly. 1982;20(1):81–84. Available from: https://www.fq.math.ca/Scanned/20-1/cohen.pdf
  6. Hagis P, Cohen GL. Some results concerning quasiperfect numbers. Journal of the Australian Mathematical Society. Series A. Pure Mathematics and Statistics. 1982;33(2):275–286. Available from: https://doi.org/10.1017/S1446788700018401
  7. Cohen GL. On odd perfect numbers (II), multiperfect numbers and quasiperfect numbers. Journal of the Australian Mathematical Society. Series A. Pure Mathematics and Statistics. 1980;29(3):369–384. Available from: https://doi.org/10.1017/S1446788700021376
  8. Tang M, Feng M. On deficient-perfect numbers. Bulletin of the Australian Mathematical Society. 2014;90(2):186–194. Available from: https://doi.org/10.1017/S0004972714000082
  9. Prasad VSR, Sunitha C, Quasiperfect O. On quasiperfect numbers. Notes on Number Theory and Discrete Mathematics. 2017;23(3):73–78. Available from: https://nntdm.net/volume-23-2017/number-3/73-78/
  10. Yamada T. Quasiperfect numbers with the same exponent. INTEGERS. 2019;19:35. Available from: https://arxiv.org/pdf/1610.01063.pdf
  11. Prasad VSR, Sunitha C. On the prime factors of a quasiperfect number. Notes on Number Theory and Discrete Mathematics. 2019;25(2):16–21. Available from: https://doi.org/10.7546/nntdm.2019.25.2.16-21
  12. Dixit U. On bounds of perfect number. Malaya Journal of Matematik. 2020;8(3):1328–1330. Available from: https://doi.org/10.26637/MJM0803/0104

Copyright

© 2022 Dixit. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Published By Indian Society for Education and Environment (iSee)

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