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Distance from n to closest prime that is different from n.
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%I #14 Dec 24 2016 01:54:49

%S 2,1,1,1,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,2,1,4,1,2,3,2,1,2,1,2,1,2,

%T 3,2,1,4,1,2,1,2,1,2,1,2,1,4,1,2,3,2,1,6,1,2,3,2,1,2,1,2,1,2,3,2,1,4,

%U 1,2,1,2,1,2,1,2,3,2,1,4,1,2,1,4,1,2,3,2,1,6,1,2,3,4,3,2,1,4,1,2,1,2,1,2,1

%N Distance from n to closest prime that is different from n.

%H T. D. Noe, <a href="/A051700/b051700.txt">Table of n, a(n) for n = 0..10000</a>

%e Closest primes to 0,1,2,3,4 are 2,2,3,2,3.

%p with(numtheory); f := n->min(nextprime(n)-n, n-prevprime(n));

%t Table[Min[NextPrime[n]-n,n-NextPrime[n,-1]],{n,0,200}] (* _Harvey P. Dale_, Mar 27 2011 *)

%Y Related sequences: A023186-A023188, A046929-A046931, A051650, A051652, A051697-A051702, A051728-A051730.

%K nonn,easy,nice

%O 0,1

%A _N. J. A. Sloane_

%E More terms from _James A. Sellers_