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A206329
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Squarefree sums of 2 successive primes.
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4
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5, 30, 42, 78, 138, 186, 210, 222, 258, 330, 390, 410, 434, 462, 618, 762, 786, 798, 906, 930, 946, 966, 978, 1002, 1030, 1230, 1290, 1334, 1374, 1410, 1446, 1482, 1518, 1542, 1606, 1722, 1758, 1770, 1794, 1830, 1866, 1878, 1938, 1974, 2006, 2022, 2190, 2226
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OFFSET
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1,1
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COMMENTS
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Intersection of A001043 and A005117, both infinite, but is their intersection infinite?
Also note that the only prime is a(1)=5 and there are no semiprimes (products of 2 primes A001358).
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LINKS
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EXAMPLE
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MAPLE
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N:= 1000: # to get the first N terms
count:= 0:
p:= 2:
while count < N do
pp:= nextprime(p);
if numtheory:-issqrfree(p+pp) then
count:= count+1;
A[count]:= p+pp;
fi;
p:= pp;
od:
seq(A[i], i=1..N);
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MATHEMATICA
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PROG
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(PARI) p=2; forprime(q=3, 1e4, if(issquarefree(p+q), print1(p+q", ")); p=q) \\ Charles R Greathouse IV, Feb 08 2012
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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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