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 A065312 #18 Jul 02 2018 03:12:54
%S A065312 7,11,19,23,37,41,47,53,59,61,73,79,83,89,101,103,113,127,137,139,149,
%T A065312 151,163,167,173,179,193,197,199,211,227,229,241,251,257,263,271,277,
%U A065312 283,293,307,311,317,331,337,347,349,353,367,373,389,397,419,421,433
%N A065312 Primes which occur exactly once in A065308 (prime(n - pi(n))).
%C A065312 In A065308 each odd prime seems to appear once or twice. Prime 2 arises there 3 times.
%H A065312 Harry J. Smith, <a href="/A065312/b065312.txt">Table of n, a(n) for n = 1..1000</a>
%t A065312 With[{s = Array[Prime[# - PrimePi[#]] &, 120]}, Most@ Select[Split[s], Length@ # == 1 &][[All, 1]] ] (* _Michael De Vlieger_, Jun 19 2018 *)
%o A065312 (PARI) { n=0; p=1; f=2; m=1; for (i=1, 10^9, a=0; p=nextprime(p + 1); while (p==f, a++; m++; f=prime(m - primepi(m))); if (a==1, write("b065312.txt", n++, " ", p); if (n==1000, return)) ) } \\ _Harry J. Smith_, Oct 16 2009
%Y A065312 Cf. A000040, A000720, A054546, A065308, A065309, A065310, A065311.
%K A065312 nonn
%O A065312 1,1
%A A065312 _Labos Elemer_, Oct 29 2001