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A214063
a(n) is the least m > 0 such that Fibonacci(n)+m and n-m are not relatively prime.
3
1, 2, 3, 4, 1, 2, 1, 8, 9, 5, 1, 2, 1, 14, 5, 16, 1, 2, 1, 5, 10, 1, 1, 2, 1, 2, 2, 28, 1, 2, 1, 10, 33, 6, 1, 2, 1, 38, 4, 5, 1, 2, 1, 44, 5, 1, 1, 2, 1, 2, 1, 21, 1, 2, 1, 7, 1, 58, 1, 2, 1, 62, 3, 64, 1, 2, 1, 68, 69, 1, 1, 2, 1, 2, 5, 76, 1, 1, 1, 5, 40, 82, 1, 2, 1, 28, 2, 10, 1, 2
OFFSET
1,2
LINKS
EXAMPLE
gcd(8+1, 6-1) = 1 and gcd(8+2, 6-2) = 2, so that a(6) = 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, 150}]
CROSSREFS
Sequence in context: A118310 A073057 A084310 * A078978 A322424 A309198
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jul 25 2012
STATUS
approved