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%I #13 Jan 31 2020 13:39:06
%S 4,4,4,6,6,4,4,6,6,6,4,6,4,6,4,4,4,14,4,6,10,6,6,4,6,6,10,4,4,4,6,10,
%T 6,6,6,6,4,10,14,4,4,14,6,10,4,6,6,6,4,6,4,10,10,6,4,6,4,4,4,4,6,6,10,
%U 6,6,6,10,6,6,6,6,4,10,4,6,6,4,6,10,10,6,6,4,6,4,4,14,10,10,4,10,14,4,4,14
%N Differences between consecutive primes that are twice primes.
%C 11 - 7 = 4 = double 2, the first entry in the table.
%H Robert Israel, <a href="/A098013/b098013.txt">Table of n, a(n) for n = 1..10000</a>
%p R:= NULL: count:= 0:
%p q:= 2: p:= 3:
%p while count < 100 do
%p q:= p; p:= nextprime(p);
%p if isprime((p-q)/2) then
%p count:= count+1; R:= R, p-q
%p fi
%p od:
%p R; # _Robert Israel_, Jun 05 2018
%t Select[Differences[Prime[Range[500]]],PrimeQ[#/2]&] (* _Harvey P. Dale_, Jan 31 2020 *)
%o (PARI) f(n) = for(x=1,n,y=prime(x+1)-prime(x);if(isprime(y\2),print1(y",")))
%Y Cf. A100484 (twice primes).
%K easy,nonn
%O 1,1
%A _Cino Hilliard_, Sep 09 2004
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