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A138698
Primes p such that 54*p-1, 54*p+1 and 60*p-1, 60*p+1 are twin primes.
6
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
OFFSET
1,1
LINKS
EXAMPLE
54*1093 - 1 = 59021, 54*1093 + 1 = 59023; 60*1093 - 1 = 65579, 60*1093 + 1 = 65581; ...
MATHEMATICA
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]&] (* Harvey P. Dale, Sep 22 2017 *)
PROG
(Magma) [p: p in PrimesUpTo(10000)| IsPrime(54*p-1) and IsPrime(54*p+1) and IsPrime(60*p-1) and IsPrime(60*p+1)]; // Vincenzo Librandi, Nov 24 2010
CROSSREFS
Sequence in context: A174422 A255838 A253234 * A342390 A252520 A023698
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from Vincenzo Librandi, Apr 01 2010
STATUS
approved