A138698 revision #13
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A138698
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Primes p such that 54*p-1, 54*p+1 and 60*p-1, 60*p+1 are twin primes.
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6
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1093, 1777, 1933, 4073, 11117, 42533, 42937, 59263, 80473, 90677, 98323, 109717, 111427, 120917, 138893, 157627, 170603, 207367, 227627, 241333, 250753, 296687, 305423, 332303, 346277, 359563, 360907, 367163, 371617, 376307, 404837, 446417
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OFFSET
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1,1
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LINKS
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EXAMPLE
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54*1093 - 1 = 59021, 54*1093 + 1 = 59023; 60*1093 - 1 = 65579, 60*1093 + 1 = 65581; ...
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MATHEMATICA
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a=54; b=60; Select[Prime[Range[14^4]], PrimeQ[a*#-1]&&PrimeQ[a*#+1]&&PrimeQ[b*#-1]&&PrimeQ[b*#+1]&]
Select[Prime[Range[40000]], AllTrue[{54#+1, 54#-1, 60#+1, 60#-1}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Sep 22 2017 *)
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PROG
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(Magma) [p: p in PrimesUpTo(1000)| IsPrime(54*p-1) and IsPrime(54*p+1) and IsPrime(60*p-1) and IsPrime(60*p+1)] // Vincenzo Librandi, Nov 24 2010
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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