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 A062558 #16 Feb 19 2024 10:32:16 %S A062558 2,2,3,3,3,4,3,4,4,4,3,6,3,4,5,5,3,6,3,6,5,4,3,8,4,4,5,6,3,8,3,6,5,4, %T A062558 5,9,3,4,5,8,3,8,3,6,7,4,3,10,4,6,5,6,3,8,5,8,5,4,3,12,3,4,7,7,5,8,3, %U A062558 6,5,8,3,12,3,4,7,6,5,8,3,10,6,4,3,12,5,4,5,8,3,12,5,6,5,4,5,12,3,6,7,9,3 %N A062558 Number of nonisomorphic cyclic subgroups of dihedral group with 2n elements. %H A062558 Antti Karttunen, <a href="/A062558/b062558.txt">Table of n, a(n) for n = 1..1001</a> %F A062558 a(n) = A000005(n) + A000035(n) = tau(n)+(n mod 2), where tau(n) = the number of divisors of n. %o A062558 (PARI) a(n) = numdiv(n) + (n % 2) \\ _Michel Marcus_, Jun 17 2013 %Y A062558 Cf. A000005, A000045, A023645, A062249 (labeled case). %Y A062558 One more than A076984. %K A062558 nonn %O A062558 1,1 %A A062558 _Vladeta Jovovic_, Jul 03 2001