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A214719
Least m>0 such that 6^n-m and n-m are relatively prime.
0
2, 1, 1, 1, 1, 5, 1, 3, 1, 1, 2, 1, 1, 1, 1, 3, 1, 1, 1, 1, 2, 3, 1, 1, 1, 3, 1, 1, 1, 1, 2, 1, 1, 1, 1, 5, 1, 1, 1, 1, 3, 1, 1, 1, 1, 3, 1, 1, 1, 3, 2, 1, 1, 1, 1, 3, 1, 1, 1, 1, 2, 1, 1, 3, 1, 5, 1, 1, 1, 1, 3, 1, 1, 1, 1, 3, 1, 5, 1, 1, 2, 1, 1, 1, 1, 3, 2
OFFSET
1,1
EXAMPLE
gcd(6^8-1,7) = 7, gcd(6^8-2,6) = 2, gcd(6^8-3,5) = 1, so a(8) = 3.
MATHEMATICA
Table[m = 1; While[GCD[5^n - m, n - m] != 1, m++]; m, {n, 1, 140}]
CROSSREFS
Cf. A214716.
Sequence in context: A275069 A181937 A233836 * A356299 A327858 A307372
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jul 27 2012
STATUS
approved