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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 (list; graph; refs; listen; history; text; internal format)
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

Vincenzo Librandi, Table of n, a(n) for n = 1..1500

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

Adjacent sequences:  A199215 A199216 A199217 * A199219 A199220 A199221

KEYWORD

nonn

AUTHOR

Brad Clardy, Nov 04 2011

STATUS

approved

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Last modified September 25 13:37 EDT 2021. Contains 347654 sequences. (Running on oeis4.)