%I #38 Sep 08 2022 08:44:43
%S 1,2,5,11,25,55,125,279,625,1397,3125,6987,15625,34938,78125,174692,
%T 390625,873464,1953125,4367320,9765625,21836601,48828125,109183006,
%U 244140625,545915033,1220703125,2729575167
%N Powers of sqrt(5) rounded down.
%C a(n) is the total length (rounded down to integer) of the elements of a variant of a 5-element fractal after n iterations, starting with 5 elements, each of whose length is 1/5 (in some units). See illustration in the Links. - _Kival Ngaokrajang_, Feb 26 2015
%H Vincenzo Librandi, <a href="/A017919/b017919.txt">Table of n, a(n) for n = 0..1000</a>
%H Kival Ngaokrajang, <a href="/A017919/a017919_3.pdf">Illustration of initial terms</a>
%t Floor[(Sqrt[5])^Range[0,40]] (* _Vincenzo Librandi_, Nov 20 2011 *)
%o (PARI) a(n)=sqrtint(5^n) \\ _Charles R Greathouse IV_, Nov 18 2011
%o (Magma) [Floor(Sqrt(5^n)): n in [0..40]]; // _Vincenzo Librandi_, Nov 20 2011
%Y Cf. A017920, A017921.
%K nonn
%O 0,2
%A _N. J. A. Sloane_
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