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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.

A287302 Primes that can be generated by the concatenation in base 4, in ascending order, of two consecutive integers read in base 10.

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%I A287302 #8 May 24 2017 09:13:16
%S A287302 11,103,137,239,1171,1301,1951,2081,2341,2731,2861,3121,3251,3511,
%T A287302 16963,17477,20047,21589,23131,26729,30841,34439,40093,43177,43691,
%U A287302 45233,46261,60139,61681,63737,270601,272651,278801,291101,295201,297251,315701,321851,325951
%N A287302 Primes that can be generated by the concatenation in base 4, in ascending order, of two consecutive integers read in base 10.
%e A287302 2 and 3 in base 4 are 2 and 3 and concat(2,3) = 23 in base 10 is 11;
%e A287302 6 and 7 in base 4 are 12 and 13 and concat(12,13) = 1213 in base 10 is 103.
%p A287302 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,4),i=1..1000);
%t A287302 With[{b = 4}, Select[Map[FromDigits[Flatten@ IntegerDigits[#, b], b] &, Partition[Range@ 320, 2, 1]], PrimeQ]] (* _Michael De Vlieger_, May 23 2017 *)
%Y A287302 Cf. A000040, A030458.
%K A287302 nonn,base,easy
%O A287302 1,1
%A A287302 _Paolo P. Lava_, May 23 2017