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A199218
Prime XOR couples of A199217.
3
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
OFFSET
1,1
COMMENTS
The terms are listed in generated, not numerical, order so that coupled terms in A199217 have the same index value.
LINKS
PROG
(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;
CROSSREFS
Cf. A199217.
Sequence in context: A147098 A109291 A340067 * A062700 A330835 A249378
KEYWORD
nonn
AUTHOR
Brad Clardy, Nov 04 2011
STATUS
approved