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 A280726 #15 Jan 08 2017 11:42:43 %S A280726 0,0,1,1,1,1,2,1,2,1,4,1,2,2,1,1,1,2,5,1,2,4,5,1,4,2,5,2,3,1,4,1,4,1, %T A280726 2,2,5,5,2,1,4,2,9,4,2,5,6,1,9,4,1,2,6,5,4,2,5,3,8,1,4,4,5,1,2,4,7,1, %U A280726 5,2,7,2,5,5,4,5,4,2,7,1,7,4,10,2,1,9,3,4,5,2,5,5,4,6,5,1,2,9,4,4,7,1,8,2,2,6,12,5,7 %N A280726 a(n) = A049501(phi(n)). %C A280726 a(n) = Major index (1st definition) of the total numbers <=n and prime to n i.e., phi(n). %H A280726 Indranil Ghosh, <a href="/A280726/b280726.txt">Table of n, a(n) for n = 1..10000</a> %H A280726 Indranil Ghosh, <a href="/A280726/a280726.txt">Python Program to generate the sequence</a> %F A280726 a(n) = A049501(A000010(n)). %e A280726 For n = 10, phi(n) = 4 and major index (1st definition) of 4 = 1. So a(n) = 1. %Y A280726 Cf. A000010, A049501, A280306, A280531. %K A280726 nonn %O A280726 1,7 %A A280726 _Indranil Ghosh_, Jan 07 2017