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 A276201 #9 Feb 16 2025 08:33:36
%S A276201 19,233,2351,235699,23571103,2357111297,235711131709,23571113171891,
%T A276201 2357111317192243,235711131719232929,23571113171923293127,
%U A276201 2357111317192329313727,235711131719232931374061,23571113171923293137414303,2357111317192329313741434739,235711131719232931374143475271
%N A276201 Largest prime < A019518(n).
%C A276201 The complement of A074366.
%H A276201 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PreviousPrime.html">Previous Prime</a>
%F A276201 a(n) = A151799(A019518(n)).
%F A276201 a(n) = A000040(A000720(A019518(n)-1)).
%e A276201 a(5) = 235699, because this is the largest prime less than 235711 (concatenation of first 5 primes, written in decimal system).
%t A276201 Table[NextPrime[FromDigits[Flatten[IntegerDigits[Prime[Range[n]]]]], -1], {n, 2, 17}]
%Y A276201 Cf. A000040, A000720, A019518, A074366, A151799.
%K A276201 nonn,base
%O A276201 2,1
%A A276201 _Ilya Gutkovskiy_, Aug 24 2016