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A153414
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Larger of twin prime pairs such that p1*p2+average_of_twin_prime_pair=prime.
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1
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5, 7, 31, 61, 139, 181, 241, 421, 619, 1051, 1609, 1699, 1789, 2269, 2311, 2731, 3259, 3391, 3529, 3769, 4159, 4219, 4339, 4801, 5641, 5869, 6661, 6691, 6871, 6961, 7489, 7549, 7591, 8539, 8629, 8971, 9631, 9859, 9931, 10459, 11119, 11971, 12541, 13339
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OFFSET
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1,1
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COMMENTS
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3*5+4=19 prime, 5*7+6=41 prime, 29*31+30=929 prime, ...
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LINKS
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Harvey P. Dale, Table of n, a(n) for n = 1..1000
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MATHEMATICA
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lst={}; Do[p1=Prime[n]; p2=Prime[n+1]; If[p2-p1==2, a=p1*p2+(p1+1); If[PrimeQ[a], AppendTo[lst, p2]]], {n, 7!}]; lst
Transpose[Select[Select[Partition[Prime[Range[1600]], 2, 1], Last[#]- First[#] == 2&], PrimeQ[Times@@#+Mean[#]]&]][[2]] (* Harvey P. Dale, Jan 23 2012 *)
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CROSSREFS
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Cf. A099349, A153374, A153375, A153376, A153377, A153378, A153379, A153406, A153407, A153408, A153409, A153410, A153413
Sequence in context: A025095 A025114 A090935 * A284405 A232237 A104815
Adjacent sequences: A153411 A153412 A153413 * A153415 A153416 A153417
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KEYWORD
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nonn
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AUTHOR
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Vladimir Joseph Stephan Orlovsky, Dec 25 2008
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STATUS
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approved
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