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A178766
Values of gcd(Fibonacci(n), Fibonacci(n+1)+1) sorted with no repeats.
2
1, 2, 3, 5, 7, 13, 18, 34, 47, 89, 123, 233, 322, 610, 843, 1597, 2207, 4181, 5778, 10946, 15127, 28657, 39603, 75025, 103682, 196418, 271443, 514229, 710647, 1346269, 1860498, 3524578, 4870847, 9227465, 12752043, 24157817, 33385282, 63245986, 87403803
OFFSET
1,2
LINKS
FORMULA
G.f.: (x^5 + x^4 - 2*x^2 - x)/(-x^4 + 3*x^2 - 1). - Alois P. Heinz, Dec 28 2010
MAPLE
a:= n-> `if` (n<2, n, (Matrix (4, (i, j)-> if i+1=j then 1 elif i=4 then [-1, 0, 3, 0][j] else 0 fi)^(n-1). <<2, 2, 3, 5>>)[1, 1]): seq (a(n), n=1..40); # Alois P. Heinz, Dec 28 2010
MATHEMATICA
Take[Union@Table[GCD[Fibonacci[n], Fibonacci[n+1]+1], {n, 1000}], 60]
GCD[#[[1]], #[[2]]+1]&/@Partition[Fibonacci[Range[100]], 2, 1]//Union (* Harvey P. Dale, Sep 22 2016 *)
CROSSREFS
Mix terms of A001519 and A005248. Cf. A063726.
Sequence in context: A076047 A245640 A365274 * A362778 A362779 A077316
KEYWORD
nonn
AUTHOR
STATUS
approved