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A060265
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Largest prime less than 2n.
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13
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3, 5, 7, 7, 11, 13, 13, 17, 19, 19, 23, 23, 23, 29, 31, 31, 31, 37, 37, 41, 43, 43, 47, 47, 47, 53, 53, 53, 59, 61, 61, 61, 67, 67, 71, 73, 73, 73, 79, 79, 83, 83, 83, 89, 89, 89, 89, 97, 97, 101, 103, 103, 107, 109, 109, 113, 113, 113, 113, 113, 113, 113, 127, 127, 131
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OFFSET
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2,1
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COMMENTS
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a(n) = A007917(2*n) = A255313(n-1,1) = A255316(n-1,1) = A006530(A255427(n)). - Reinhard Zumkeller, Feb 22 2015
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LINKS
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Harry J. Smith, Table of n, a(n) for n = 2..1000
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MAPLE
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seq (prevprime(2*i+1), i=2..256);
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MATHEMATICA
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Table[NextPrime[2 n, -1], {n, 2, 66}] (* Michael De Vlieger, Jul 04 2016 *)
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PROG
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(PARI) for (n=2, 1000, write("b060265.txt", n, " ", precprime(2*n)); ) \\ Harry J. Smith, Jul 03 2009
(Haskell)
a060265 = a007917 . (* 2) -- Reinhard Zumkeller, Feb 22 2015
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CROSSREFS
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Apart from initial term, same as A060308.
Cf. A020482, A049653, A088631, A007917, A005843, A255313.
Sequence in context: A260940 A037464 A302564 * A172365 A297709 A242999
Adjacent sequences: A060262 A060263 A060264 * A060266 A060267 A060268
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KEYWORD
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nonn,easy
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AUTHOR
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Labos Elemer, Mar 23 2001
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STATUS
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approved
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