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 A217140 #8 Oct 02 2012 12:16:44 %S A217140 24,24,24,24,36,24,24,24,24,36,24,24,24,24,36,24,24,24,24,36,24,24,24, %T A217140 24,36,24,24,24,24,36,24,24,24,24,60,24,24,24,24,36,24,24,24,24,36,24, %U A217140 24,24,24,36,24,24,24,24,36,24,24,24,24,36,24,24,24,24,36 %N A217140 a(n) = m/n where m is the least number divisible by n such that phi(m) = phi(m+6n). %H A217140 Michel Marcus, <a href="/A217140/b217140.txt">Table of n, a(n) for n = 1..1000</a> %e A217140 A179188(1)=24 is divisible by 1 and the quotient is 24, so a(1)=24. %e A217140 A217139(1)=48 is divisible by 2 and the quotient is 24, so a(2)=24. %e A217140 The first solution to phi(n)=phi(n+18) to be divisible by 3 is 72 and the quotient is 24, so a(3)=24. %Y A217140 Cf. A007015, A179188, A217139, A217141, A217068. %K A217140 nonn %O A217140 1,1 %A A217140 _Michel Marcus_ and _Jonathan Sondow_, Oct 01 2012