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A138660
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Primes p such that (12*p - 1, 12*p + 1) and (18*p - 1, 18*p + 1) are twin primes.
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1
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29, 1051, 6719, 9059, 10501, 27749, 27791, 36749, 51421, 83761, 86729, 108751, 115249, 120049, 124139, 124529, 138629, 148861, 152839, 162091, 169009, 176609, 178249, 178921, 202481, 203141, 209621, 228199, 232681, 244411, 302779, 309259
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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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29 is a term since it is a prime and (12*29 - 1, 12*29 + 1) = (347, 349) and (18*29 - 1, 18*29 + 1) = (521, 523) are twin primes.
1051 is a term since it is a prime and (12*1051 - 1, 12*1051+ 1) = (12611, 12613) and (18*1051 - 1, 18*1051 + 1) = (18917, 18919) are twin primes.
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MATHEMATICA
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a=12; b=18; Select[Prime[Range[14^4]], PrimeQ[a*#-1]&&PrimeQ[a*#+1]&&PrimeQ[b*#-1]&&PrimeQ[b*#+1]&]
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PROG
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(Magma) [p: p in PrimesUpTo(1000)| IsPrime(12*p-1) and IsPrime(12*p+1) and IsPrime(18*p-1) and IsPrime(18*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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