An algorithm for counting the number of periodic points of a family of polynomials

نویسندگان

1 Department of Mathematics, Faculty of Mathematical Sciences, Alzahra University,Tehran, I. R. Iran

2 Department of Mathematics, Faculty of Basic Sciences, Shahid Rajaee Teacher Training University, Tehran, I. R. Iran

doi
10.22061/jdma.2024.11165.1084
چکیده

In this paper we consider the family $f_a(x) = axd(x − 1) + x$ when $a < 0$ is a real number and d ≥ 2 is an even integer. The function fa has a unique positive critical point. By decreasing the parameter a, the behavior of the orbit of this critical point changes. In this paper we consider two cases. In the first case the orbit of the positive critical point converges to 0 and in the second case the positive critical point is mapped to a repelling periodic point of period 2. In each case we give a recursive formula to determine the number of the periodic points of fa. Also, in each case we introduce an invariant set on which fa is chaotic. We employ conjugacy map and symbolic dynamics in our investigations.