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 A108031 Inverse Moebius transform of Lucas numbers (A000032). 0

%I

%S 2,3,5,7,9,17,20,36,52,86,125,220,324,542,855,1400,2209,3635,5780,

%T 9439,15150,24602,39605,64328,103691,168086,271495,439750,710649,

%U 1150794,1860500,3011749,4870975,7883406,12752070,20637077,33385284,54024302

%N Inverse Moebius transform of Lucas numbers (A000032).

%e a(4)=7 because the divisors of 4 are 1,2,4 and the first, second and fourth Lucas numbers are 2, 1 and 4, respectively, having sum 7.

%p with(combinat): with(numtheory): f:=n->2*fibonacci(n)-fibonacci(n-1): g:=proc(n) local div: div:=divisors(n): sum(f(div[j]),j=1..tau(n)) end: seq(g(n),n=1..45);

%t Table[Total[LucasL[#]&/@(Divisors[n]-1)],{n,40}] (* _Harvey P. Dale_, Dec 08 2014 *)

%Y Cf. A000032, A100107.

%K nonn

%O 1,1

%A _Emeric Deutsch_, May 31 2005

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Last modified June 7 02:48 EDT 2020. Contains 334836 sequences. (Running on oeis4.)