English

On Polynomial Pairs of Integers

Number Theory 2016-04-18 v2

Abstract

The reversal of a positive integer AA is the number obtained by reading AA backwards in its decimal representation. A pair (A,B)(A,B) of positive integers is said to be palindromic if the reversal of the product A×BA \times B is equal to the product of the reversals of AA and of BB. A pair (A,B)(A,B) of positive integers is said to be polynomial if the product A×BA \times B can be performed without carry. In this paper, we use polynomial pairs in constructing and in studying the properties of palindromic pairs. It is shown that polynomial pairs are always palindromic. It is further conjectured that, provided that neither AA nor BB is itself a palindrome, all palindromic pairs are polynomial. A connection is made with classical topics in recreational mathematics such as reversal multiplication, palindromic squares, and repunits.

Keywords

Cite

@article{arxiv.1210.7593,
  title  = {On Polynomial Pairs of Integers},
  author = {Martianus Frederic Ezerman and Bertrand Meyer and Patrick Sole},
  journal= {arXiv preprint arXiv:1210.7593},
  year   = {2016}
}

Comments

13 pages, 3 tables, errors are corrected, some proofs are made more explicit