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A138697
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Primes p such that 42*p-1, 42*p+1 and 48*p-1, 48*p+1 are twin primes.
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5
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31, 331, 2971, 4421, 4861, 5309, 5441, 20431, 22381, 23459, 28151, 33911, 37061, 37699, 47491, 66449, 75821, 82799, 83701, 86131, 91961, 106621, 110059, 112289, 130811, 134669, 135461, 141601, 144461, 152959, 153701, 167311, 167759, 171049
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| 42*31-1=1301, 42*31+1=1303; 48*31-1=1487, 48*31+1=1489; ...
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MATHEMATICA
| a=42; b=48; Select[Prime[Range[14^4]], PrimeQ[a*#-1]&&PrimeQ[a*#+1]&&PrimeQ[b*#-1]&&PrimeQ[b*#+1]&]
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PROG
| (MAGMA) [p: p in PrimesUpTo(1000)| IsPrime(42*p-1) and IsPrime(42*p+1) and IsPrime(48*p-1) and IsPrime(48*p+1)] [From V.Librandi, Nov 24 2010]
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CROSSREFS
| Sequence in context: A142382 A137318 A029813 * A186071 A033175 A123568
Adjacent sequences: A138694 A138695 A138696 * A138698 A138699 A138700
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KEYWORD
| nonn
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AUTHOR
| Vladimir Orlovsky (4vladimir(AT)gmail.com), May 15 2008
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EXTENSIONS
| More terms from Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Apr 01 2010
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