A216813 - OEIS

%I #31 Aug 11 2014 22:45:49

%S 0,3,6,18,39,96,201,582,1220,2590,5345,10919,21859,44167,88629,178050,

%T 356598,715084,1431514,2866876,5736311,11480839,22966942,45949687,

%U 91910241,183852468,367726473,735517466,1471078571,2942286009,5884661772,11769583511,23539346216,47079214312,94158788295

%N Sum of tail length of S over all 2^n strings S consisting of n 2's and 3's.

%C "Tail length" is defined in A216730.

%H Benjamin Chaffin and N. J. A. Sloane, <a href="/A216813/b216813.txt">Table of n, a(n) for n = 1..40</a>

%H B. Chaffin, J. P. Linderman, N. J. A. Sloane and Allan Wilks, <a href="http://arxiv.org/abs/1212.6102">On Curling Numbers of Integer Sequences</a>, arXiv:1212.6102, Dec 25 2012.

%H B. Chaffin, J. P. Linderman, N. J. A. Sloane and Allan Wilks, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL16/Sloane/sloane3.html">On Curling Numbers of Integer Sequences</a>, Journal of Integer Sequences, Vol. 16 (2013), Article 13.4.3.

%H <a href="/index/Cu#curling_numbers">Index entries for sequences related to curling numbers</a>

%F a(n) = A094005(n) - n*2^n.

%F Up to n=32, the average tail length a(n)/2^n seems to be approaching a number around 2.74.

%Y Cf. A094005, A216730.

%K nonn

%O 1,2

%A _N. J. A. Sloane_, Sep 18 2012 - Sep 21 2012, Oct 23 2012