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A214718
Least m>0 such that 5^n-m and n-m are relatively prime.
1
2, 1, 2, 2, 4, 1, 2, 1, 2, 2, 4, 1, 2, 1, 2, 3, 4, 1, 2, 1, 2, 2, 4, 1, 2, 1, 2, 2, 4, 1, 2, 1, 2, 2, 4, 2, 2, 1, 2, 2, 4, 1, 4, 1, 2, 2, 4, 1, 2, 1, 2, 2, 4, 1, 2, 1, 2, 3, 4, 1, 2, 1, 2, 2, 4, 1, 2, 1, 2, 3, 4, 1, 2, 1, 2, 2, 4, 2, 2, 1, 2, 2, 4, 1, 2, 1, 2
OFFSET
1,1
LINKS
EXAMPLE
gcd(5^7-1,6) = 2, gcd(5^7-2,5) = 1, so a(7) = 2.
MATHEMATICA
Table[m = 1; While[GCD[5^n - m, n - m] != 1, m++]; m, {n, 1, 140}]
CROSSREFS
Cf. A214716.
Sequence in context: A377230 A255723 A309022 * A367970 A345161 A321319
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jul 27 2012
STATUS
approved