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A119381
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Primes p(n) for which (p(n-1) + p(n+2)) / p(n) = 2.
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7
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37, 67, 277, 479, 613, 631, 809, 1297, 1471, 1607, 1663, 1721, 1783, 1867, 1901, 1931, 1993, 2137, 2377, 2411, 2521, 2683, 2797, 2879, 3359, 3571, 3917, 4391, 4513, 4621, 5413, 5437, 5477, 5647, 6299, 7321, 7393, 7873, 7901, 8087, 8819, 9007, 10301
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..43.
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FORMULA
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a(n) = Prime(A119382(n)), where Prime(n) is the n-th prime. - Stefan Steinerberger, Jul 26 2006
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EXAMPLE
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In the ordered set of primes we have ...271,277,281,283... and (271+283)/277 = 2, therefore 277 belongs in this sequence.
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MATHEMATICA
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Prime[Select[Range[2, 1500], (Prime[ # - 1] + Prime[ # + 2])/(Prime[ # ]) == 2 &]] (* Stefan Steinerberger, Jul 26 2006 *)
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CROSSREFS
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Cf. A119382.
Cf. A119382.
Sequence in context: A141163 A063461 A105462 * A138396 A335484 A155087
Adjacent sequences: A119378 A119379 A119380 * A119382 A119383 A119384
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KEYWORD
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easy,nonn
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AUTHOR
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Axel Harvey, Jul 25 2006
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EXTENSIONS
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More terms from Stefan Steinerberger, Jul 26 2006
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STATUS
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approved
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