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A138696
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Primes p such that 30*p-1, 30*p+1 and 36*p-1, 36*p+1 are twin primes.
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6
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2, 5, 457, 1013, 2683, 5413, 46307, 51287, 67433, 99223, 116443, 146603, 149837, 159017, 172373, 181277, 187987, 199523, 248477, 249503, 259163, 278903, 279337, 286333, 293893, 294803, 304813, 312527, 315037, 335743, 379433, 392593, 393713
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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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30*2-1=59, 30*2+1=61; 36*2-1=71, 36*2+1=73;
30*5-1=149, 30*5+1=151; 36*5-1=179, 36*5+1=181; ...
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MATHEMATICA
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a=30; b=36; Select[Prime[Range[14^4]], PrimeQ[a*#-1]&&PrimeQ[a*#+1]&&PrimeQ[b*#-1]&&PrimeQ[b*#+1]&]
Select[Prime[Range[35000]], AllTrue[Flatten[{30#+{1, -1}, 36#+{1, -1}}], PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jan 20 2015 *)
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PROG
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(Magma) [p: p in PrimesUpTo(1000000)| IsPrime(30*p-1) and IsPrime(30*p+1) and IsPrime(36*p-1) and IsPrime(36*p+1)]; // Vincenzo Librandi, Nov 24 2010
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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