This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A060173 #12 Jan 05 2025 19:51:36
%S A060173 1,1,1,2,1,6,1,12,10,30,1,139,1,252,231,920,1,3780,1,10250,5601,32076,
%T A060173 1,149390,2126,400036,173692,1475642,1,6196651,1,19113136,5864915,
%U A060173 68635494,201405,289525026,1,930138540,208267554,3469290971,1,14075005210,1,47994721225,7683440470
%N A060173 Number of orbits of length n under a map whose periodic points are counted by A056045.
%C A060173 The sequence A056045 records the number of points of period n under a map. The number of orbits of length n for this map gives the sequence above.
%H A060173 Y. Puri and T. Ward, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL4/WARD/short.html">Arithmetic and growth of periodic orbits</a>, J. Integer Seqs., Vol. 4 (2001), #01.2.1.
%H A060173 Yash Puri and Thomas Ward, <a href="https://web.archive.org/web/2024*/https://www.fq.math.ca/Scanned/39-5/puri.pdf">A dynamical property unique to the Lucas sequence</a>, Fibonacci Quarterly, Volume 39, Number 5 (November 2001), pp. 398-402.
%F A060173 a(n) = (1/n)* Sum_{ d divides n } mu(d)*A056045(n/d).
%e A060173 a(7) = 1 since the map whose periodic points are counted by A056045 has 1 fixed point and 8 points of period 7, hence 1 orbits of length 7.
%o A060173 (PARI) a056045(n) = sumdiv(n, d, binomial(n, d));
%o A060173 a(n) = (1/n)*sumdiv(n, d, moebius(d)*a056045(n/d)); \\ _Michel Marcus_, Sep 11 2017
%Y A060173 Cf. A056045, A060164, A060165, A060166, A060167, A060168, A060169, A060170, A060171, A060172.
%K A060173 easy,nonn
%O A060173 1,4
%A A060173 _Thomas Ward_, Mar 13 2001
%E A060173 More terms from _Michel Marcus_, Sep 11 2017