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A215808
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Primes of the form 2*prime(k) - prime(k+1).
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3
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3, 3, 17, 41, 47, 67, 151, 167, 199, 227, 251, 257, 347, 367, 557, 587, 601, 607, 641, 647, 727, 941, 971, 1051, 1091, 1097, 1117, 1181, 1217, 1277, 1361, 1427, 1447, 1447, 1487, 1487, 1499, 1607, 1697, 1741, 1747, 1741, 1777, 1877, 1901, 2087, 2143, 2281
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OFFSET
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1,1
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COMMENTS
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Corresponding values of k: 3, 4, 9, 15, 16, 21, 37, 40, 47, 51, 55, 56, 71, 74, 103 (A216075).
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LINKS
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EXAMPLE
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k=3: 2*5-7=3, k=4: 2*7-11=3, k=9: 2*23-29=17.
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MATHEMATICA
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pr=Prime[Range[1000]]; s=Select[2*Most[pr]-Rest[pr], PrimeQ]
Select[2#[[1]]-#[[2]]&/@Partition[Prime[Range[500]], 2, 1], PrimeQ] (* Harvey P. Dale, Feb 25 2017 *)
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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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