A287302 Primes that can be generated by the concatenation in base 4, in ascending order, of two consecutive integers read in base 10.
11, 103, 137, 239, 1171, 1301, 1951, 2081, 2341, 2731, 2861, 3121, 3251, 3511, 16963, 17477, 20047, 21589, 23131, 26729, 30841, 34439, 40093, 43177, 43691, 45233, 46261, 60139, 61681, 63737, 270601, 272651, 278801, 291101, 295201, 297251, 315701, 321851, 325951
Offset: 1
Examples
2 and 3 in base 4 are 2 and 3 and concat(2,3) = 23 in base 10 is 11; 6 and 7 in base 4 are 12 and 13 and concat(12,13) = 1213 in base 10 is 103.
Programs
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Maple
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);
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Mathematica
With[{b = 4}, Select[Map[FromDigits[Flatten@ IntegerDigits[#, b], b] &, Partition[Range@ 320, 2, 1]], PrimeQ]] (* Michael De Vlieger, May 23 2017 *)