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%I #11 Sep 16 2020 05:01:27
%S 1,1,1,1,1,1,1,1,1,1,1,3,1,1,1,3,1,1,1,1,1,1,1,3,1,1,3,1,1,1,3,1,1,1,
%T 1,1,3,1,1,1,1,3,1,1,3,3,1,1,1,1,1,1,1,1,1,1,3,5,7,5,3,1,1,1,1,3,1,1,
%U 1,3,5,3,1,1,1,3,1,1,3,1,1,1,1,3,1,1,3,1,1,1,3,5,3,1,1,1,1,1,1,3,5,5,3,1,1
%N Distance of 2n from the closest prime.
%F a(n) = min(A049653(n), A060266(n)). - _Michel Marcus_, Sep 16 2020
%e n=13, 2n=26 surrounded by 23 and 29 which are from 26 in equal distance of 3 and min{3,3}=3=a(13).
%p with(numtheory): [seq(min(nextprime(2*i)-2*i, 2*i-prevprime(2*i)), i=2...256)];
%t a[n_] := Min[NextPrime[2*n] - 2*n, 2*n - NextPrime[2*n, -1]]; Array[a, 100, 2] (* _Amiram Eldar_, Sep 16 2020 *)
%o (PARI) a(n) = min(2*n - precprime(2*n-1), nextprime(2*n+1) - 2*n); \\ _Michel Marcus_, Sep 16 2020
%Y Cf. A020482, A049653, A051702, A059959, A060266.
%K nonn
%O 2,12
%A _Labos Elemer_, Mar 23 2001
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