A214714 - OEIS

%I #6 Jul 30 2012 17:38:22

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

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

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

%N Least m>0 such that prime(n)-m and n-m are relatively prime.

%C Does every positive integer occur?

%H Clark Kimberling, <a href="/A214714/b214714.txt">Table of n, a(n) for n = 1..1000</a>

%e gcd(16,6) = 2, gcd(15,5) = 5, gcd(14,4) = 2, gcd(13,3) = 1, so a(7) = 4.

%t Table[m = 1; While[GCD[Prime[n] - m, n - m] != 1, m++]; m, {n, 1, 140}]

%Y Cf. A214052.

%K nonn,easy

%O 1,3

%A _Clark Kimberling_, Jul 27 2012