%I #25 May 19 2019 01:43:54

%S 2,4,12,24,12,24,24,60,12,48,36,84,12,24,84,12,24,60,24,132,120,24,24,

%T 96,36,168,96,24,12,48,72,48,36,96,204,84,120,12,24,36,108,240,12,120,

%U 240,60,24,60,36,24,96,48,36,264,156,156,24,60,84,60,72,48,12,120,24

%N First differences of sequence of consecutive safe primes.

%H G. C. Greubel, <a href="/A059322/b059322.txt">Table of n, a(n) for n = 0..5000</a>

%F a(n) = A005385(n+1) - A005385(n). - corrected by _Harvey P. Dale_, Jan 12 2011 and _Zak Seidov_, Sep 19 2016

%e 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).

%t Differences[Select[Prime[Range[500]],PrimeQ[(#-1)/2]&]] (* _Harvey P. Dale_, Jan 12 2011 *)

%Y Cf. A005385, A033299.

%K nonn

%O 0,1

%A _Labos Elemer_, Jan 26 2001