login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A258575 Numbers n such that Lucas(n)-Fibonacci(n) is squarefree. 1

%I #23 Sep 08 2022 08:46:12

%S 0,2,3,5,6,8,9,11,12,14,15,17,18,20,21,23,24,27,29,30,32,33,35,36,38,

%T 39,41,42,44,45,47,48,50,53,54,56,59,60,62,63,65,66,68,69,71,72,74,75,

%U 77,78,80,81,83,84,86,87,89,90,93,95,96,98,99,102,104,105

%N Numbers n such that Lucas(n)-Fibonacci(n) is squarefree.

%C These numbers belong to the sequence A007494 (see _Chai Wah Wu_ argumentation in A258574).

%C Also numbers n such that 2*Fibonacci(n-1) is squarefree. [_Bruno Berselli_, Jun 05 2015]

%C A258575(n) = A258574(n+1)-1. - _Chai Wah Wu_, Jun 09 2015

%t Select[Range[0, 200], SquareFreeQ[LucasL[#] - Fibonacci[#]] &]

%o (Magma) [0] cat [n: n in [2..150] | IsSquarefree(Lucas(n)-Fibonacci(n))];

%o (Sage) [n for n in (0..110) if is_squarefree(2*fibonacci(n-1))] # _Bruno Berselli_, Jun 05 2015

%Y Cf. A000032, A000045, A005117, A007494, A037918, A118658, A258574.

%K nonn,easy,less

%O 1,2

%A _Vincenzo Librandi_, Jun 04 2015

%E Name corrected by _Bruno Berselli_, Jun 05 2015

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 13 15:48 EDT 2024. Contains 375142 sequences. (Running on oeis4.)