English

On primitive weird numbers of the form $2^k p q$

Number Theory 2015-04-13 v1

Abstract

We say a natural number~nn is abundant if σ(n)>2n\sigma(n)>2n, where σ(n)\sigma(n) denotes the sum of the divisors of~nn. The aliquot parts of~nn are those divisors less than~nn, and we say that an abundant number~nn is pseudoperfect if there is some subset of the aliquot parts of~nn which sum to~nn. We say~nn is weird if~nn is abundant but not pseudoperfect. We call a weird number~nn primitive if none of its aliquot parts are weird. We find all primitive weird numbers of the form 2kpq2^kpq (p<qp<q being odd primes) for 1k141\le k\le14. We also find primitive weird numbers of the same form, larger than any previously published.

Keywords

Cite

@article{arxiv.1504.02761,
  title  = {On primitive weird numbers of the form $2^k p q$},
  author = {Douglas E. Iannucci},
  journal= {arXiv preprint arXiv:1504.02761},
  year   = {2015}
}