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A193687
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Numbers n such that the sum of n-th average of a twin prime pair and the n-th twin prime is also a twin prime.
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1
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1, 2, 3, 4, 5, 6, 8, 10, 11, 13, 15, 22, 24, 32, 35, 36, 43, 44, 53, 55, 59, 67, 68, 70, 71, 73, 78, 82, 86, 108, 109, 113, 129, 132, 147, 151, 152, 154, 155, 159, 164, 165, 166, 168, 172, 173, 181, 193, 206, 211, 229, 231, 241, 260, 262, 271, 272, 277, 286
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listen;
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internal format)
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OFFSET
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1,2
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LINKS
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EXAMPLE
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a(8)=10 because 108+41=149 where 149 is a twin primes and A014574(10)=108, A001097(10)=41.
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MAPLE
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isA001097 := 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 n from 1 to 300 do
printf("%d, ", n);
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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