OFFSET
1,2
LINKS
Clark Kimberling, Table of n, a(n) for n = 1..1000
EXAMPLE
gcd(2^6-1-1,6-1) = gcd(62,5) = 1
gcd(2^6-1-2,6-2) = gcd(61,4) = 1
gcd(2^6-1-3,6-3) = gcd(60,3) = 3,
so that a(6) = 3.
MATHEMATICA
b[n_] := 2^n-1; c[n_] := n;
Table[m = 1; While[GCD[b[n] + m, c[n] - m] == 1, m++]; m, {n, 1, 100}]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jul 22 2012
STATUS
approved