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A186312
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There appear to be at least n lower twin primes between x/2 and x for all x >= a(n).
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2
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11, 59, 101, 149, 179, 227, 569, 599, 641, 809, 821, 1019, 1049, 1061, 1289, 1319, 1427, 1451, 1481, 1667, 1787, 1871, 1877, 1931, 1949, 2081, 2129, 2237, 2657, 2687, 2711, 2999, 3251, 3257, 3299, 3359, 3461, 3467, 3527, 3539, 3767, 3917, 4001, 4019, 4091
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OFFSET
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1,1
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COMMENTS
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The name says "appear" because this sequence assumes that the twin prime conjecture is true. Note that every term is also a lower twin prime. This sequence for lower twin primes is like the Ramanujan primes (A104272) for the sequence of prime numbers. However, in this case, we do not know if there are an infinite number of twin primes. It appears that A001359(2n) < a(n) < A001359(4n).
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LINKS
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CROSSREFS
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Cf. A001359 (lower twin primes), A088018 (counts the lower twin primes between n-1 and 2(n-1)).
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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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