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A347280
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Let P1>3, P2, P3, P4 be 4 consecutive primes with P3-P2 = 2. a(n) = P2 is the earliest occurrence of the 4-tuple with min(P2-P1, P4-P3) = 2*n, or 0 if no such constellation exists.
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2
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11, 29, 0, 419, 521, 0, 1931, 6449, 0, 10037, 43541, 0, 10007, 28349, 0, 107507, 280409, 0, 261167, 173429, 0, 569321, 913637, 0, 1598447, 1789091, 0, 1349531, 5317451, 0, 17282051, 25844561, 0, 10851161, 28582787, 0, 36126917, 14318657, 0, 60117947, 42062717
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OFFSET
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2,1
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COMMENTS
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The "irregular" constellation 3, 5, 7, 11 is intentionally excluded.
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LINKS
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EXAMPLE
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a(2) = 11, because min(11-7, 17-13) = 4 is the earliest occurrence of the minimum gap of 2*2 = 4 adjacent to a pair of twin primes.
a(3) = 29: the constellation 23, 29, 31, 37 has min(29-23, 37-31) = 2*3 = 6, whereas the preceding constellations 7, 11, 13, 19, and 13, 17, 19, 23 don't yield a minimum of 6.
a(5) = 419: 409, 419, 421, 431 leads to the earliest occurrence of the minimum adjacent gap of 2*5.
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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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