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Numbers k that divide Lucas(k) + 1.
3

%I #22 Aug 20 2021 04:20:53

%S 1,2,4,8,15,16,32,64,128,256,323,368,512,736,1024,1472,2048,2944,4096,

%T 4879,5655,5888,6479,7055,8192,8464,9879,10815,11663,11776,12935,

%U 16384,16928,18407,19043,23407,23552,31535,32768,33856,34943,35207,35296

%N Numbers k that divide Lucas(k) + 1.

%C The powers of 2 (A000079) are in the sequence. - _Michel Lagneau_, Feb 09 2015

%H Giovanni Resta, <a href="/A094398/b094398.txt">Table of n, a(n) for n = 1..1000</a>

%t Select[Range[40000],Divisible[LucasL[#]+1,#]&] (* _Harvey P. Dale_, Apr 13 2011 *)

%o (PARI) is(n)=(Mod([0,1;1,1],n)^n*[2;1])[1,1]==-1 \\ _Charles R Greathouse IV_, Nov 04 2016

%Y Cf. A000079, A000204, A005845, A094402.

%K nonn

%O 1,2

%A _Eric Rowland_, May 01 2004