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%I #18 Sep 08 2022 08:46:00
%S 3,7,13,31,29,59,53,113,109,103,233,227,211,193,499,491,487,461,457,
%T 431,421,419,409,401,389,1013,967,937,929,919,883,877,863,859,853,827,
%U 809,797,2039,2011,2003,1979,1949,1901,1879,1871,1823,1789,1783,1753,1699
%N Prime XOR couples of A199217.
%C The terms are listed in generated, not numerical, order so that coupled terms in A199217 have the same index value.
%H Vincenzo Librandi, <a href="/A199218/b199218.txt">Table of n, a(n) for n = 1..1500</a>
%o (Magma)
%o XOR := func<a, b | Seqint([ (adigs[i] + bdigs[i]) mod 2 : i in [1..n]], 2)
%o where adigs := Intseq(a, 2, n)
%o where bdigs := Intseq(b, 2, n)
%o where n := 1 + Ilog2(Max([a, b, 1]))>;
%o for i in [1 .. 12] do
%o xornum:=2^(i)-2;
%o for j := 2^(i) +1 to 3*2^(i-1) by 2 do
%o xorcouple:=XOR(j,xornum);
%o if (IsPrime(j) and IsPrime(xorcouple)) then xorcouple;
%o end if;
%o end for;
%o "****";
%o end for;
%Y Cf. A199217.
%K nonn
%O 1,1
%A _Brad Clardy_, Nov 04 2011
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