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 A219249 #18 Dec 23 2024 14:53:43
%S A219249 1,3,5,2,4,6,8,13,14,7,9,20,24,16,18,30,25,27,29,41,31,35,36,38,50,52,
%T A219249 42,46,47,49,61,63,53,57,58,64,68,69,70,72,74,75,79,202,92,94,96,81,
%U A219249 83,85,86,97,203,130,205,207,241,302,413,131,303,135,242,414,136,138,141,305,246,142,416,146,147,247,249,250
%N A219249 Lexicographically earliest sequence of positive integers such that the absolute difference of any two adjacent digits is prime.
%C A219249 See A219250 for the version allowing nonnegative integers, i.e., starting with a(1)=0.
%C A219249 See A219248 for the numbers which occur in this sequence, and A219251 for the complement.
%H A219249 E. Angelini, <a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan/2013-April/011035.html">Any digit-pair in S sums to a prime</a>, SeqFan list, Apr 11 2013
%o A219249 (PARI) {A219249(n,a=[1],u=0)=while(#a<n,u+=1<<a[#a];for(t=a[1]+1,9e9,bittest(u,t)&next;my(d=concat(a[#a]%10,digits(t)));for(i=2,#d,isprime(abs(d[i-1]-d[i]))||next(2));a=concat(a,t);break));a}
%Y A219249 Cf. A182175, A182177, A182178.
%K A219249 nonn,base
%O A219249 1,2
%A A219249 _Eric Angelini_ and _M. F. Hasler_, Apr 11 2013