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A071157 The zero-free, right-to-left factorial walk encoding for each rooted plane tree encoded by A014486. Sequence A071155 shown with factorial expansion (A007623). 4

%I #12 Oct 17 2015 22:23:55

%S 0,1,11,21,111,211,121,221,321,1111,2111,1211,2211,3211,1121,2121,

%T 1221,2221,3221,1321,2321,3321,4321,11111,21111,12111,22111,32111,

%U 11211,21211,12211,22211,32211,13211,23211,33211,43211,11121,21121,12121

%N The zero-free, right-to-left factorial walk encoding for each rooted plane tree encoded by A014486. Sequence A071155 shown with factorial expansion (A007623).

%C Apart from the initial term (0, which encodes the null tree), if we scan the digits from the right (the least significant digit which is always 1) to the left (the most significant), then each successive digit to the left is at most one greater than the previous and never less than one.

%C Note: this finite decimal representation works only up to the 23712nd term, as the 23713rd such walk is already (10,9,8,7,6,5,4,3,2,1). The sequence A071158 shows the initial portion of this sequence sorted.

%H C. Banderier, A. Denise, P. Flajolet, M. Bousquet-Mélou et al., <a href="http://algo.inria.fr/banderier/Papers/DiscMath99.ps">Generating Functions for Generating Trees</a>, Discrete Mathematics 246(1-3), March 2002, pp. 29-55.

%H A. Karttunen, <a href="http://www.iki.fi/~kartturi/matikka/Nekomorphisms/gatomorf.htm">Gatomorphisms and other excursions amidst the plane trees and parenthesizations</a> (Includes the complete Scheme program for computing this sequence)

%F a(n) = A007623(A071155(n)).

%Y Corresponding Łukasiewicz words: A071153.

%Y Essentially the same as A071159 but with digits reversed.

%K nonn,fini

%O 0,3

%A _Antti Karttunen_, May 14 2002

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Last modified April 16 12:52 EDT 2024. Contains 371711 sequences. (Running on oeis4.)