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 A287312 #6 May 28 2017 09:35:26
%S A287312 11,31,41,61,71,739,821,1231,1559,1723,2297,2543,2707,2789,2953,3527,
%T A287312 3691,4019,5003,5167,5413,5659,5741,5987,6151,6397,65701,66431,67891,
%U A287312 72271,76651,81031,81761,83221,85411,100741,102931,108041,121181,135781,136511,140891
%N A287312 Primes that can be generated by the concatenation in base 9, in ascending order, of two consecutive integers read in base 10.
%e A287312 1 and 2 in base 9 are 1 and 2 and concat(1,2) = 12 in base 10 is 11;
%e A287312 9 and 10 in base 9 are 10 and 11 and concat(10,11) = 1011 in base 10 is 739.
%p A287312 with(numtheory): P:= proc(q,h) local a,b,c,d,k,n; a:=convert(q+1,base,h); b:=convert(q,base,h); c:=[op(a),op(b)]; d:=0; for k from nops(c) by -1 to 1 do d:=h*d+c[k]; od; if isprime(d) then d; fi; end: seq(P(i,9),i=1..1000);
%t A287312 With[{b = 9}, Select[Map[FromDigits[Flatten@ IntegerDigits[#, b], b] &, Partition[Range@ 200, 2, 1]], PrimeQ]] (* _Michael De Vlieger_, May 25 2017 *)
%Y A287312 Cf. A000040, A030458.
%K A287312 nonn,base,easy
%O A287312 1,1
%A A287312 _Paolo P. Lava_, May 24 2017