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%I #17 Feb 06 2017 22:01:40
%S 1,1,2,2,2,2,2,2,4,2,2,4,2,2,4,6,2,2,4,2,2,4,4,6,4,2,2,2,2,4,4,4,2,2,
%T 2,2,6,4,4,6,2,2,2,2,2,2,12,4,2,2,4,2,2,6,6,6,2,2,4,2,2,10,4,2,2,4,6,
%U 6,2,2,4,6,6,6,4,4,6,4,4,8,2,2,2,2,4,4,6,4,2,2,4,8,4,4,4,4,6,2,2,6,6,6,6,2
%N Distance from n-th prime to closest prime.
%H T. D. Noe, <a href="/A051702/b051702.txt">Table of n, a(n) for n = 1..10000</a>
%e Closest primes to 2,3,5,7,11 are 3,2,3,5,13.
%t a[n_] := Min[(p = Prime[n]) - NextPrime[p, -1], NextPrime[p] - p]; Table[a[n], {n, 1, 104}] (* _Jean-François Alcover_, May 27 2013 *)
%t Join[{1},Min[Differences[#]]&/@Partition[Prime[Range[110]],3,1]] (* _Harvey P. Dale_, Sep 23 2016 *)
%o (PARI) a(n,p=prime(n))=min(p-precprime(p-1),nextprime(p+1)-p) \\ _Charles R Greathouse IV_, Feb 06 2017
%Y Related sequences: A023186-A023188, A046929-A046931, A051650, A051652, A051697-A051702, A051728-A051730.
%Y A046929(n+1) + 1.
%K nonn,easy,nice
%O 1,3
%A _N. J. A. Sloane_
%E More terms from _James A. Sellers_