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A059322
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First differences of sequence of consecutive safe primes.
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2
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2, 4, 12, 24, 12, 24, 24, 60, 12, 48, 36, 84, 12, 24, 84, 12, 24, 60, 24, 132, 120, 24, 24, 96, 36, 168, 96, 24, 12, 48, 72, 48, 36, 96, 204, 84, 120, 12, 24, 36, 108, 240, 12, 120, 240, 60, 24, 60, 36, 24, 96, 48, 36, 264, 156, 156, 24, 60, 84, 60, 72, 48, 12, 120, 24
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OFFSET
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0,1
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LINKS
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FORMULA
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EXAMPLE
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Except for (5,7) and (7,11), all terms are divisible by 12, since safe primes are congruent to 5 modulo 6 except 7 and safe_prime+6 is not a safe prime. Closest safe primes differ by 12 like (11,23) or (83207,83219).
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MATHEMATICA
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Differences[Select[Prime[Range[500]], PrimeQ[(#-1)/2]&]] (* Harvey P. Dale, Jan 12 2011 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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