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 A287307 #8 May 24 2017 09:14:07
%S A287307 13,41,443,739,887,1109,9547,11717,14321,16057,17359,18661,19963,
%T A287307 22133,22567,23869,25171,28643,29077,31247,32983,33851,35153,40361,
%U A287307 43399,44267,44701,45569,287933,290527,303497,306091,311279,319061,337219,345001,389099,391693
%N A287307 Primes that can be generated by the concatenation in base 6, in descending order, of two consecutive integers read in base 10.
%e A287307 1 and 2 in base 6 are 1 and 2 and concat(2,1) = 21 in base 10 is 13;
%e A287307 5 and 6 in base 6 are 5 and 10 and concat(10,5) = 105 in base 10 is 41.
%p A287307 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,6),i=0..1000);
%t A287307 With[{b = 6}, Select[Map[FromDigits[Flatten@ IntegerDigits[#, b], b] &, Reverse /@ Partition[Range[0, 302], 2, 1]], PrimeQ]] (* _Michael De Vlieger_, May 23 2017 *)
%Y A287307 Cf. A000040, A052089.
%K A287307 nonn,base,easy
%O A287307 1,1
%A A287307 _Paolo P. Lava_, May 23 2017