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 A320719 #9 Feb 22 2020 20:17:19
%S A320719 1879,3732,4059,4135,4714,5355,5948,6160,6841,7434,7724,7746,7952,
%T A320719 7980,8081,8269,8580,9303,9395,9971,10045,10305,10968,11023,11135,
%U A320719 11251,11338,11399,11515,11807,11888,11901,12089,12374,12488,13277,13447,14497,14802,15086,15089,15350,15612,15785
%N A320719 Indices of primes followed by a gap (distance to next larger prime) of 42.
%C A320719 Indices of the primes listed in A134120.
%H A320719 Harvey P. Dale, <a href="/A320719/b320719.txt">Table of n, a(n) for n = 1..3000</a>
%H A320719 <a href="/index/Pri#gaps">Index entries for primes, gaps between</a>.
%F A320719 a(n) = A000720(A134120(n)).
%t A320719 Position[Differences[Prime[Range[16000]]],42]//Flatten (* _Harvey P. Dale_, Feb 22 2020 *)
%o A320719 (PARI) A(N=100,g=42,p=2,i=primepi(p)-1,L=List())={forprime(q=1+p,,i++; if(p+g==p=q, listput(L,i); N--||break));Vec(L)} \\ returns the list of first N terms of the sequence
%Y A320719 Cf. A029707, A029709 (analog for gaps 2 & 4), A320701, A320702, ... A320720 (analog for gaps 6, 8, ..., 44), A116493 (gap 70), A116496 (gap 100), A116497 (gap 200), A116495 (gap 210).
%Y A320719 Equals A000720 o A134120.
%Y A320719 Indices of 42's in A001223.
%Y A320719 Row 21 of A174349.
%K A320719 nonn
%O A320719 1,1
%A A320719 _M. F. Hasler_, Oct 19 2018