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A248483
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Consider two consecutive primes {p,q} such that P=2p+q and Q=2q+p are both prime. The sequence gives primes Q.
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3
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13, 19, 47, 181, 317, 367, 677, 743, 811, 1031, 1489, 2347, 2381, 2477, 2749, 2777, 4729, 4951, 5189, 5657, 5851, 6287, 7297, 7583, 8287, 8867, 8969, 9001, 9049, 9463, 10103, 10733, 11261, 12713, 13109, 14009, 14747, 17393, 17749, 18679, 19081, 20399, 21157, 22541
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(1)=13 because p=3, q=5 and P=11 and Q=13 are both prime.
a(3)=47 because p=13, q=17 and P=43 and Q=47 are both prime.
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MAPLE
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R:= NULL: count:= 0:
q:= 2:
while count < 100 do
p:= q; q:= nextprime(q);
if isprime(2*p+q) and isprime(p+2*q) then
count:= count+1; R:= R, p+2*q
fi
od:
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MATHEMATICA
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Select[Table[If[PrimeQ[2*Prime[j-1] + Prime[j]] && PrimeQ[Prime[j-1] + 2*Prime[j]], Prime[j-1] + 2*Prime[j], 0], {j, 2, 2000}], #!=0&] (* Vaclav Kotesovec, Oct 08 2014 *)
2#[[2]]+#[[1]]&/@Select[Partition[Prime[Range[1000]], 2, 1], AllTrue[{2#[[1]]+#[[2]], 2#[[2]]+ #[[1]]}, PrimeQ]&] (* Harvey P. Dale, Jan 10 2024 *)
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PROG
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(PARI) listQ(nn) = {forprime(p=2, nn, q = nextprime(p+1); if (isprime(2*p+q) && isprime(Q=2*q+p), print1(Q, ", ")); ); } \\ Michel Marcus, Oct 07 2014
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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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