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A029708
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Numbers k such that k-2 and k+2 are consecutive primes.
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6
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9, 15, 21, 39, 45, 69, 81, 99, 105, 111, 129, 165, 195, 225, 231, 279, 309, 315, 351, 381, 399, 441, 459, 465, 489, 501, 615, 645, 675, 741, 759, 771, 825, 855, 861, 879, 885, 909, 939, 969, 1011, 1089, 1095, 1215, 1281, 1299, 1305, 1425, 1431
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OFFSET
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1,1
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COMMENTS
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All terms are multiples of 3. Minimal first difference is 6. - Zak Seidov, May 15 2013
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LINKS
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FORMULA
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MATHEMATICA
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Select[Range[9, 1432, 6], PrimeQ[#-2]&&PrimeQ[#+2]&] (* Zak Seidov, May 15 2013 - just for terms in DATA *)
Mean/@Select[Partition[Prime[Range[300]], 2, 1], #[[2]]-#[[1]]==4&] (* Harvey P. Dale, Feb 15 2020 *)
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PROG
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(Magma) [k:k in [1..1500]| IsPrime(k-2) and NextPrime(k-2) eq k+2 ] // Marius A. Burtea, Jan 24 2019
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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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