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 A173207 Cubefree Fibonacci numbers which are not squarefree. 2
 75025, 12586269025, 225851433717, 2111485077978050, 4660046610375530309, 354224848179261915075, 43566776258854844738105, 114059301025943970552219, 42230279526998466217810220532898, 1672445759041379840132227567949787325 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Subsequence of A061899. [R. J. Mathar, Feb 16 2010] Apparently contains Fibonacci(25*m), m>0. - Ralf Stephan, Jan 26 2014 LINKS Chai Wah Wu, Table of n, a(n) for n = 1..21 FORMULA A000045 INTERSECT A067259. MATHEMATICA f[n_]:=Union[Last/@FactorInteger[n]][[ -1]]; lst={}; Do[fibo=Fibonacci[n]; If[f[fibo]==2, AppendTo[lst, fibo]], {n, 3, 2*5!}]; lst PROG (Python) from sympy import factorint A173207_list = [] a, b = 1, 2 for _ in range(10**2): ....if max(factorint(b).values()) == 2: ........A173207_list.append(b) ....a, b = b, a + b # Chai Wah Wu, Jun 08 2015 CROSSREFS Sequence in context: A210051 A179252 A045731 * A182809 A182393 A347848 Adjacent sequences: A173204 A173205 A173206 * A173208 A173209 A173210 KEYWORD nonn AUTHOR Vladimir Joseph Stephan Orlovsky, Feb 12 2010 EXTENSIONS Converted cross-references to a formula - R. J. Mathar, Feb 16 2010 STATUS approved

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Last modified June 19 03:10 EDT 2024. Contains 373492 sequences. (Running on oeis4.)