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A329151
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Primes p such that (3*p+q)/2 and (p+3*q)/2 are prime, where q is the next prime after p.
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2
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5, 29, 47, 139, 293, 557, 607, 647, 659, 709, 773, 809, 811, 863, 1117, 1171, 1187, 1801, 2129, 2467, 2477, 2549, 2917, 3023, 3229, 3329, 3389, 3469, 3593, 3617, 3833, 4261, 4363, 5791, 5849, 6269, 6781, 6949, 7069, 7703, 8273, 9397, 9973, 10141, 10343, 10369, 10529, 10657, 11059, 11329, 13063
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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a(3)=47 is a term because it is prime, the next prime is 53, and (3*47+53)/2 = 97 and (47+3*53)/2 = 103 are both prime.
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MAPLE
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Primes:= [seq(ithprime(i), i=1..10000)]:
Res:= NULL:
for i from 2 to nops(Primes)-1 do
p:= Primes[i]; q:= Primes[i+1]; c:= (p+q)/2;
if isprime(p+c) and isprime(q+c) then
Res:= Res, p
fi
od:
Res;
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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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