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A075731
Fibonacci numbers F(k) for k squarefree (A005117).
1
1, 1, 2, 5, 8, 13, 55, 89, 233, 377, 610, 1597, 4181, 10946, 17711, 28657, 121393, 514229, 832040, 1346269, 3524578, 5702887, 9227465, 24157817, 39088169, 63245986, 165580141, 267914296, 433494437, 1836311903, 2971215073
OFFSET
1,3
EXAMPLE
10 is squarefree and fibonacci(10)=55, 11 is squarefree and fibonacci(11)=89.
MAPLE
with(combinat, fibonacci): fib_dsk := proc(n); if (numtheory[issqrfree](n)='true') then RETURN(fibonacci(n)); fi; end: seq(fib_dsk(i), i=1..100);
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jani Melik, Oct 07 2002
STATUS
approved