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 A088847 #22 Oct 11 2024 10:45:18 %S A088847 1,1,3,4,4,6,6,8,9,8,10,12,12,14,15,16,16,18,18,20,21,20,22,24,25,24, %T A088847 27,28,28,30,30,32,33,32,35,36,36,36,39,40,40,42,42,44,45,46,46,48,49, %U A088847 50,51,52,52,54,55,56,57,56,58,60,60,62,63,64,65,66,66,68,69,70,70,72,72,74,75,76,77,78,79,80,81,82,82,84,85,86,87,88,89,90,91,92,93,94,95,96,97,98,99,100 %N A088847 a(n) = sigma(A087979(n)) / phi(A087979(n)). %C A088847 Note that A087979(n) is a balanced number (A020492), hence this sequence is well-defined. - _Max Alekseyev_, Oct 10 2024 %C A088847 For all n, a(n) <= n and a(n) divides A299822(n). - _Max Alekseyev_, Oct 11 2024 %e A088847 While A088830 includes special balanced numbers, A087979 does not include per definition. Nevertheless, it seems that A087979 consists only of balanced numbers. This is provable at least for special cases. %Y A088847 Cf. A000010, A000203, A087979, A020492, A088830, A299822. %K A088847 nonn %O A088847 1,3 %A A088847 _Labos Elemer_, Nov 17 2003 %E A088847 a(24)-a(35) from _Amiram Eldar_, Dec 05 2019 (calculated from the data at A087979) %E A088847 Terms a(36) onward from _Max Alekseyev_, Oct 10 2024