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 A064777 #23 Jun 15 2021 08:06:01
%S A064777 1,2,3,18,42,95,524,273585,1735537,4406057,4406063,4406188,4406196,
%T A064777 4406341,4406539,4406541,28703894,73694240,73694281,73694287,73694360,
%U A064777 73694363,73694410,3287860772,3287860773,3287860880,3287860889,3287860895,3287860897
%N A064777 Numbers k such that prime(k) - pi(k) is divisible by k.
%e A064777 k = 18 is a term: prime(18) = 61, pi(18) = 7, and (61-7)/18 = 54/18 = 3.
%t A064777 Do[ If[ IntegerQ[ (Prime[n] - PrimePi[n])/n ], Print[n]], {n, 1, 6*10^7} ]
%t A064777 Select[Range[5000000],Divisible[Prime[#]-PrimePi[#],#]&] (* _Harvey P. Dale_, Aug 12 2013 *)
%o A064777 (PARI) isok(k) = ((prime(k) - primepi(k)) % k) == 0; \\ _Michel Marcus_, Jun 15 2021
%Y A064777 Cf. A000040, A000720, A065139, A111181.
%K A064777 nonn
%O A064777 1,2
%A A064777 _Labos Elemer_ and _Robert G. Wilson v_, Oct 18 2001
%E A064777 a(18)-a(23) from _Donovan Johnson_, Apr 23 2010
%E A064777 a(24)-a(29) from _Donovan Johnson_, Oct 17 2012