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 A065136 #6 Sep 01 2018 17:44:49 %S A065136 3,9,11,13,28,34,37,43,121,336,341,351,356,361,1081,1087,1135,3060, %T A065136 3074,3081,3088,3095,8409,8425,8441,8457,8465,8473,23527,23536,24301, %U A065136 64541,64581,64591,64601,64611,64651,64661,64691,64701,64711,64721 %N A065136 Numbers n such that n = pi(n)*k + 1 for some k. %C A065136 Solutions to Mod[n,PrimePi[n]] = 1, i.e. A065134(n) = 1. %H A065136 Giovanni Resta, <a href="/A065136/b065136.txt">Table of n, a(n) for n = 1..1172</a> %e A065136 n=28: Pi(28)=9 and 28=3*Pi(28)+1, so 28 is here; n=27 is present in A057809. A large proportion of A057809(m)+1 numbers (but not all of them) arise in this sequence. Numbers from A057809 arise in clusters [see grouping around 8450, 64650, 480900 etc.] %Y A065136 A000720, A065134, A057809. %K A065136 nonn %O A065136 1,1 %A A065136 _Labos Elemer_, Oct 15 2001