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%I #11 Sep 16 2020 05:00:54
%S 2,2,4,4,2,4,4,2,4,4,6,6,6,2,6,6,6,4,4,2,4,4,6,6,6,6,6,6,2,6,6,6,4,4,
%T 2,6,6,6,4,4,6,6,6,8,8,8,8,4,4,2,4,4,2,4,4,14,14,14,14,14,14,14,4,4,6,
%U 6,6,2,10,10,10,10,10,2,6,6,6,6,6,6,4,4,6,6,6,6,6,6,2,10,10,10,10,10,2,4
%N Difference between 2 closest primes surrounding 2n.
%H Michael De Vlieger, <a href="/A060267/b060267.txt">Table of n, a(n) for n = 2..10000</a>
%e a(3) = 2 because the closest primes to 2*3 = 6 are (5,7) and the difference between these is 2. - _Michael De Vlieger_, Nov 02 2017
%p with(numtheory): [seq(nextprime(2*i)-prevprime(2*i),i=2..256)];
%t Array[Subtract @@ NextPrime[#, {1, -1}] &[2 #] &, 96, 2] (* _Michael De Vlieger_, Nov 02 2017 *)
%t NextPrime[#]-NextPrime[#,-1]&/@(2*Range[2,100]) (* _Harvey P. Dale_, Nov 07 2017 *)
%o (PARI) a(n) = nextprime(2*n+1) - precprime(2*n-1); \\ _Michel Marcus_, Sep 16 2020
%Y Cf. A020482, A049653, A060264, A060265, A060266, A060268.
%K nonn
%O 2,1
%A _Labos Elemer_, Mar 23 2001
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