A216813 Sum of tail length of S over all 2^n strings S consisting of n 2's and 3's.

0, 3, 6, 18, 39, 96, 201, 582, 1220, 2590, 5345, 10919, 21859, 44167, 88629, 178050, 356598, 715084, 1431514, 2866876, 5736311, 11480839, 22966942, 45949687, 91910241, 183852468, 367726473, 735517466, 1471078571, 2942286009, 5884661772, 11769583511, 23539346216, 47079214312, 94158788295

Offset

1,2

Comments

"Tail length" is defined in A216730.

Links

Benjamin Chaffin and N. J. A. Sloane, Table of n, a(n) for n = 1..40

B. Chaffin, J. P. Linderman, N. J. A. Sloane and Allan Wilks, On Curling Numbers of Integer Sequences, arXiv:1212.6102, Dec 25 2012.

B. Chaffin, J. P. Linderman, N. J. A. Sloane and Allan Wilks, On Curling Numbers of Integer Sequences, Journal of Integer Sequences, Vol. 16 (2013), Article 13.4.3.

Index entries for sequences related to curling numbers

Formula

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

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

Crossrefs

Cf. A094005, A216730.

Sequence in context: A160505 A081150 A362014 * A356766 A181037 A222856

Adjacent sequences: A216810 A216811 A216812 * A216814 A216815 A216816

Keyword

nonn

Author

N. J. A. Sloane, Sep 18 2012 - Sep 21 2012, Oct 23 2012

Status

approved