English

Palindromic concatenations of two distinct repdigits in Narayana's cows sequence

Number Theory 2024-01-01 v1

Abstract

Let (Nn)n0(N_{n})_{n\ge 0} be Narayana's cows sequence given by a recurrence relation Nn+3=Nn+2+Nn N_{n+3}=N_{n+2}+N_n for all n0 n\ge 0 , with initial conditions N0=0 N_0=0 , and N1=N2=1 N_1= N_2=1 . In this paper, we find all members in Narayana's cow sequence that are palindromic concatenations of two distinct repdigits. Our proofs use techniques on Diophantine approximation which include the theory of linear forms in logarithms of algebraic numbers and Baker's reduction method. We show that 595595 is the only member in Narayana's cow sequence that is a palindromic concatenation of two distinct repdigits in base 1010.

Keywords

Cite

@article{arxiv.2312.17571,
  title  = {Palindromic concatenations of two distinct repdigits in Narayana's cows sequence},
  author = {Mahadi Ddamulira and Paul Emong and Geoffrey Ismail Mirumbe},
  journal= {arXiv preprint arXiv:2312.17571},
  year   = {2024}
}

Comments

Accepted to appear in the Bulletin of the Iranian Mathematical Society (BIMS)