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 A171434 #11 Feb 25 2020 12:16:51 %S A171434 2,3,7,13,61,151,397,1153,64567,64577,480967,480979,9559867,9559897, %T A171434 9560167,189961657,189961819,189962593,189963043,189964321,189969379, %U A171434 514272779,514275401,1394193607,1394194727,1394198807,10246936003,75370121191,75370121767,75370121839 %N A171434 Primes that are congruent to 7 mod n, where n is the index of the prime. %H A171434 Giovanni Resta, <a href="/A171434/b171434.txt">Table of n, a(n) for n = 1..71</a> %t A171434 Prime@ Select[Range[10^5], Mod[Prime[#] - 7, #] == 0 &] (* _Giovanni Resta_, Feb 25 2020 *) %Y A171434 Cf. A023149, A048891, A171430, A171431, A171432. %K A171434 nonn %O A171434 1,1 %A A171434 _Vladimir Joseph Stephan Orlovsky_, Dec 09 2009 %E A171434 Missing a(1)-a(4), a(16) and beyond from _Giovanni Resta_, Feb 23 2020