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A227323
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Prime(k) such that each of the three preceding and also each of the three following primes are twin primes.
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0
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11, 1039, 2099, 4253, 9433, 9437, 62983, 62987, 72229, 72251, 91121, 386401, 392269, 392279, 495589, 495611, 626617, 663583, 663587, 754973, 873553, 908857, 909301, 909317, 909319, 909329, 972137, 1006309, 1006331, 1138393, 1138409, 1159201
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OFFSET
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1,1
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COMMENTS
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Prime(k) such that prime(k-i), i=1..3, and prime(k+i), i=1..3 are in A001097.
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LINKS
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MAPLE
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istwp := proc(n)
if isprime(n) then
if isprime(n+2) or isprime(n-2) then
true;
else
false;
end if;
else
false;
end if;
end proc:
for i from 4 do
p := ithprime(i) ;
p1 := prevprime(p) ;
if istwp(p1) then
p2 := prevprime(p1) ;
if istwp(p2) then
p3 := prevprime(p2) ;
if istwp(p3) then
p1 := nextprime(p) ;
if istwp(p1) then
p2 := nextprime(p1) ;
if istwp(p2) then
p3 := nextprime(p2) ;
if istwp(p3) then
printf("%d\n", p) ;
end if;
end if;
end if;
end if;
end if;
end if;
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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