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A214065
a(n) is the least m > 0 such that Fibonacci(n+1+m) and n-m are not relatively prime.
2
1, 2, 3, 4, 2, 2, 1, 6, 5, 1, 3, 2, 1, 5, 4, 4, 2, 2, 1, 6, 5, 1, 3, 2, 1, 5, 2, 4, 2, 2, 1, 2, 5, 1, 3, 2, 1, 5, 5, 1, 2, 2, 1, 6, 5, 1, 2, 2, 1, 5, 5, 1, 2, 2, 1, 6, 2, 1, 3, 2, 1, 2, 5, 4, 2, 2, 1, 6, 5, 1, 3, 2, 1, 5, 5, 4, 2, 1, 1, 6, 5, 1, 3, 2, 1, 5, 2, 4, 2, 2, 1, 2, 2, 1, 3, 2, 1, 5, 5
OFFSET
1,2
LINKS
EXAMPLE
gcd(F(5+1+1), 5-1) = 1 and gcd(F(5+1+2), 5-2) > 1, so that a(5) = 2.
MATHEMATICA
b[n_] := Fibonacci[n]; c[n_] := n;
Table[m = 1; While[GCD[b[n + 1 + m], c[n] - m] == 1, m++]; m, {n, 1, 120}]
CROSSREFS
Sequence in context: A299755 A323907 A375127 * A182710 A182711 A138136
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jul 25 2012
STATUS
approved