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 A075738 Squarefree Fibonacci numbers whose indices are also squarefree. 1
 1, 1, 2, 5, 13, 55, 89, 233, 377, 610, 1597, 4181, 10946, 17711, 28657, 121393, 514229, 1346269, 3524578, 5702887, 9227465, 24157817, 39088169, 63245986, 165580141, 433494437, 1836311903, 2971215073, 20365011074, 53316291173 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS EXAMPLE Fib(10)=55 is there because both 10 and 55 are squarefree. MAPLE with(combinat, fibonacci): fib_supM_dsk := proc(n); if (numtheory[issqrfree](n)='true') then if (numtheory[issqrfree](fibonacci(n))='true') then RETURN(fibonacci(n)); fi; fi; end: seq(fib_supM_dsk(i), i=1..100); MATHEMATICA Select[With[{nn=70}, Thread[{Range[nn], Fibonacci[Range[nn]]}]], AllTrue[#, SquareFreeQ]&][[All, 2]] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Apr 17 2018 *) CROSSREFS Cf. A000045, A005117, A061305, A075739. Sequence in context: A105905 A236513 A214853 * A076999 A306827 A028856 Adjacent sequences:  A075735 A075736 A075737 * A075739 A075740 A075741 KEYWORD easy,nonn AUTHOR Jani Melik, Oct 07 2002 EXTENSIONS Edited by Don Reble, Nov 05 2005 STATUS approved

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Last modified November 30 04:55 EST 2021. Contains 349418 sequences. (Running on oeis4.)