A note on the OEIS sequence A228059

Jose Arnaldo Bebita Dris and Doli-Jane Uvales Tejada
Notes on Number Theory and Discrete Mathematics
Print ISSN 1310–5132, Online ISSN 2367–8275
Volume 25, 2019, Number 1, Pages 199–205
DOI: 10.7546/nntdm.2019.25.1.199-205
Full paper (PDF, 153 Kb)

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Authors and affiliations

Jose Arnaldo Bebita Dris
Institute of Mathematics, University of the Philippines
Carlos P. Garcia Avenue, Diliman, Quezon City, Philippines

Doli-Jane Uvales Tejada
Mathematics Department, College of Natural Sciences and Mathematics
Mindanao State University, General Santos City, Philippines

Abstract

The OEIS sequence A228059 lists odd numbers of the form p1+4kr2, where p is prime of the form 1+4m, r > 1, and gcd(p, r) = 1 that are closer to being perfect than previous terms. In this note, we present the prime factorizations of the first 37 terms.

Keywords

  • Odd perfect number
  • Abundancy index
  • Deficiency

2010 Mathematics Subject Classification

  • 11A25

References

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  6. Noe, T. D., OEIS sequence A228059, http://oeis.org/A228059.
  7. Resta, G., Private communication, August 23, 2018.
  8. Resta, G., Private communication, August 24, 2018.
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  10. Sorli, R. M. (2003). Algorithms in the study of multiperfect and odd perfect numbers, Ph. D. Thesis, University of Technology, Sydney.

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Cite this paper

Dris, J. A. B. & Tejada, D.-J. U. (2019). A note on the OEIS sequence A228059. Notes on Number Theory and Discrete Mathematics, 25(1), 199-205, DOI: 10.7546/nntdm.2019.25.1.199-205.

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