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 A182177 #19 Jan 27 2021 05:31:28
%S A182177 0,2,1,4,3,8,5,6,7,41,11,12,9,20,21,14,16,50,23,25,29,43,47,49,83,85,
%T A182177 61,65,67,411,111,112,30,32,34,38,52,56,58,92,94,70,74,76,114,98,302,
%U A182177 116,120,202,121,123,89,203,205,207,412,125,211,129,212,141,143,214,147,414,149,216,161,165,230,232,167,416,502,303,234,305,238,307,430,250,252,320,256,503,258,321,292,323,294,325,298,329,432,341,434,343,438,347,470,349
%N A182177 Beginning with 0, smallest positive integer not yet in the sequence such that two adjacent digits of the sequence (also ignoring commas between terms) sum to a prime.
%C A182177 A219250 is the analog of this sequence, replacing "sum" by "absolute difference". A219249 is the same analog for A182178. A219248 is the analog of A182175 and A219251 corresponds to A219110 = terms which do not occur in this sequence, i.e., the complement of its range. - _M. F. Hasler_, Apr 12 2013
%e A182177 41 appears after 7 because 7+4 is prime and 4+1 is prime, and no other number less than 41 (not already in the sequence) satisfies this property. Example: 11 does not directly follow 7 since 7+1 is not prime.
%o A182177 (PARI) A182177_vec={(n, a=[0], 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(d[i-1]+d[i])||next(2)); a=concat(a, t); break)); a} \\ _M. F. Hasler_, Apr 11 2013
%Y A182177 Cf. A182175.
%K A182177 nonn,base,easy
%O A182177 1,2
%A A182177 _Jim Nastos_ and _Eric Angelini_, Apr 16 2012