%I #4 Jul 25 2012 18:00:59
%S 1,2,3,2,5,1,1,2,9,2,11,2,1,2,15,2,3,2,1,2,8,2,23,2,1,1,2,2,29,2,1,2,
%T 3,2,35,2,1,2,39,2,41,2,1,2,1,1,2,2,1,2,14,1,2,2,1,2,57,2,3,2,1,2,63,
%U 2,65,1,1,2,6,2,6,2,1,2,75,2,77,2,1,2,81,2
%N Least m>0 such that 2^n+m and n-m have a common divisor > 1.
%H Clark Kimberling, <a href="/A214056/b214056.txt">Table of n, a(n) for n = 1..1000</a>
%e gcd(2^4+1,4-1) = 1 and gcd(2^4+2,4-2) = 2, so a(4) = 2.
%t b[n_] := 2^n; c[n_] := n;
%t Table[m = 1; While[GCD[b[n] + m, c[n] - m] == 1, m++]; m, {n, 1, 100}]
%Y Cf. A214057.
%K nonn,easy
%O 1,2
%A _Clark Kimberling_, Jul 22 2012
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