English

On variants of Conway and Conolly's Meta-Fibonacci recursions

Combinatorics 2014-07-03 v1

Abstract

We study the recursions A(n)=A(naAk(nb))+A(Ak(nb))A(n) = A(n-a-A^k(n-b)) + A(A^k(n-b)) where a0a \geq 0, b1b \geq 1 are integers and the superscript kk denotes a kk-fold composition, and also the recursion C(n)=C(nsC(n1))+C(ns2C(n3))C(n) = C(n-s-C(n-1)) + C(n-s-2-C(n-3)) where s0s \geq 0 is an integer. We prove that under suitable initial conditions the sequences A(n)A(n) and C(n)C(n) will be defined for all positive integers, and be monotonic with their forward difference sequences consisting only of 0 and 1. We also show that the sequence generated by the recursion for A(n)A(n) with parameters (k,a,b)=(k,0,1)(k,a,b) = (k,0,1), and initial conditions A(1)=A(2)=1A(1) = A(2) = 1, satisfies A(En)=En1A(E_n) = E_{n-1} where EnE_n is defined by En=En1+EnkE_n = E_{n-1} + E_{n-k} with En=1E_n = 1 for 1nk1 \leq n \leq k.

Keywords

Cite

@article{arxiv.1407.0425,
  title  = {On variants of Conway and Conolly's Meta-Fibonacci recursions},
  author = {Abraham Isgur and Mustazee Rahman},
  journal= {arXiv preprint arXiv:1407.0425},
  year   = {2014}
}

Comments

10 pages