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A214064
a(n) is the least m > 0 such that Fibonacci(n+m) and n-m are not relatively prime.
3
5, 2, 3, 2, 1, 6, 1, 4, 3, 2, 1, 6, 5, 2, 1, 2, 1, 6, 1, 4, 3, 2, 1, 6, 5, 2, 1, 2, 1, 2, 1, 4, 3, 2, 1, 6, 5, 2, 3, 2, 1, 6, 1, 4, 3, 2, 1, 6, 5, 2, 3, 2, 1, 2, 1, 4, 3, 2, 1, 4, 5, 2, 3, 2, 1, 6, 1, 2, 3, 2, 1, 6, 5, 2, 1, 2, 1, 6, 1, 4, 3, 2, 1, 6, 5, 2, 1, 2, 1, 5, 1, 4, 3, 2, 1, 6, 5, 2, 3
OFFSET
1,1
LINKS
EXAMPLE
gcd(F(4+1), 4-1) = 1, gcd(F(4+2), 4-2) > 1, so that a(4) = 2.
MATHEMATICA
b[n_] := Fibonacci[n]; c[n_] := n;
Table[m = 1; While[GCD[b[n + m], c[n] - m] == 1, m++]; m, {n, 1, 120}]
CROSSREFS
Cf. A214063.
Sequence in context: A178566 A155551 A259027 * A343486 A098584 A081750
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jul 25 2012
STATUS
approved