OFFSET
1,1
LINKS
Clark Kimberling, Table of n, a(n) for n = 1..1000
EXAMPLE
gcd(4^6-1,5) = 5, gcd(4^6-2,4) = 2, gcd(4^6-3,3) = 1, so a(6) = 3.
MATHEMATICA
Table[m = 1; While[GCD[4^n - m, n - m] != 1, m++]; m, {n, 1, 140}]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jul 27 2012
STATUS
approved