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A199218
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Prime XOR couples of A199217.
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3
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3, 7, 13, 31, 29, 59, 53, 113, 109, 103, 233, 227, 211, 193, 499, 491, 487, 461, 457, 431, 421, 419, 409, 401, 389, 1013, 967, 937, 929, 919, 883, 877, 863, 859, 853, 827, 809, 797, 2039, 2011, 2003, 1979, 1949, 1901, 1879, 1871, 1823, 1789, 1783, 1753, 1699
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OFFSET
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1,1
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COMMENTS
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The terms are listed in generated, not numerical, order so that coupled terms in A199217 have the same index value.
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LINKS
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PROG
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(Magma)
XOR := func<a, b | Seqint([ (adigs[i] + bdigs[i]) mod 2 : i in [1..n]], 2)
where adigs := Intseq(a, 2, n)
where bdigs := Intseq(b, 2, n)
where n := 1 + Ilog2(Max([a, b, 1]))>;
for i in [1 .. 12] do
xornum:=2^(i)-2;
for j := 2^(i) +1 to 3*2^(i-1) by 2 do
xorcouple:=XOR(j, xornum);
if (IsPrime(j) and IsPrime(xorcouple)) then xorcouple;
end if;
end for;
"****";
end for;
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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