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%I #7 Jan 17 2020 10:46:40
%S 1,4,12,12,6,42,18,42,18,42,12,18,42,36,24,6,30,12,60,60,48,30,24,6,
%T 12,42,30,36,84,18,48,60,30,30,12,60,102,66,42,18,102,30,30,72,78,18,
%U 30,102,108,144,18,60,42,6,42,42,60,30,156,72,12,6,60,90,12,72,60
%N Gaps between primes p such that 2p-1 is also prime.
%H Andrew Howroyd, <a href="/A074258/b074258.txt">Table of n, a(n) for n = 1..1000</a>
%o (PARI) my(lsgp=2); forprime (p=3, 3000, if (isprime(2*p-1), print1(p-lsgp, ", "); lsgp=p))
%Y First differences of A005382.
%Y Cf. A001223.
%K nonn
%O 1,2
%A _Jon Perry_, Sep 20 2002
%E Offset corrected and terms a(34) and beyond from _Andrew Howroyd_, Jan 16 2020