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 A099008 #14 Jul 20 2018 22:27:30 %S A099008 546,903,1806,2730,6162,6510,9030,10230,12090,12246,12810,15834,20130, %T A099008 20670,23478,23790,28938,30030,30810,43134,44310,52374,56730,61230, %U A099008 71610,79170,84630,85722,88410,99330,109230,117390,132990,140910,144690,154770,164010 %N A099008 Numbers n such that the denominator of the 2n-th Bernoulli number is divisible by n but sum_{d|n} sigma(d)/phi(d) is not an integer. %C A099008 Intersection of A106741 and complement of A068991. - _Michel Marcus_, Dec 07 2013 %e A099008 The denominator of the 1806th Bernoulli number is 1806 and Sum_{d|1806} sigma(d)/phi(d) = 172/3 is not an integer. %o A099008 (PARI) lista() = {v = readvec("b106741.txt"); for (i=1, #v, vi = v[i]; if (denominator(sumdiv(vi, d, sigma(d)/eulerphi(d))) != 1, print1(vi, ", ")));} \\ _Michel Marcus_, Dec 07 2013 %Y A099008 Cf. A068991. %K A099008 nonn %O A099008 1,1 %A A099008 _Benoit Cloitre_, Nov 07 2004 %E A099008 Extended using b-file from A106741 by _Michel Marcus_, Dec 07 2013