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A173207
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Cubefree Fibonacci numbers which are not squarefree.
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2
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75025, 12586269025, 225851433717, 2111485077978050, 4660046610375530309, 354224848179261915075, 43566776258854844738105, 114059301025943970552219, 42230279526998466217810220532898, 1672445759041379840132227567949787325
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OFFSET
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1,1
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COMMENTS
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Apparently contains Fibonacci(25*m), m>0. - Ralf Stephan, Jan 26 2014
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LINKS
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FORMULA
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MATHEMATICA
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f[n_]:=Union[Last/@FactorInteger[n]][[ -1]]; lst={}; Do[fibo=Fibonacci[n]; If[f[fibo]==2, AppendTo[lst, fibo]], {n, 3, 2*5!}]; lst
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PROG
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(Python)
from sympy import factorint
a, b = 1, 2
for _ in range(10**2):
....if max(factorint(b).values()) == 2:
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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Converted cross-references to a formula - R. J. Mathar, Feb 16 2010
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STATUS
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approved
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