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 A334050 #14 Sep 13 2020 12:55:13 %S A334050 1,2,3,7,19,31,9,13,73,33,137,39,311,93,11,931,91,37,331,373,313,733, %T A334050 191,3733,319,1373,3137,333,1913,739,3119,337,193,119,3191,3739,31193, %U A334050 371,933,71,9311,9319,13733,13739,31913,7331,913,7333,19137,393,1193,3719,3371,9337,1931,1933,719,3373 %N A334050 Lexicographically earliest sequence of distinct positive integers such that the concatenation of any four successive digits forms a prime. %H A334050 Jean-Marc Falcoz, <a href="/A334050/b334050.txt">Table of n, a(n) for n = 1..500</a> %e A334050 The first terms 1, 2, 3, 7, 19, 31, 9,... form (when 4 successive digits are concatenated) the prime numbers 1237, 2371, 3719, 7193, 1931, 9319, ... %Y A334050 Cf. A091633, A337613 (same idea, 2 successive digits), A337614 (3 successive digits). %K A334050 base,nonn %O A334050 1,2 %A A334050 _Eric Angelini_ and _Jean-Marc Falcoz_, Sep 06 2020