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A080237 Start with 1 and apply the process: k-th run is 1, 2, 3, .., a(k-1)+1. +0
11
1, 1, 2, 1, 2, 1, 2, 3, 1, 2, 1, 2, 3, 1, 2, 1, 2, 3, 1, 2, 3, 4, 1, 2, 1, 2, 3, 1, 2, 1, 2, 3, 1, 2, 3, 4, 1, 2, 1, 2, 3, 1, 2, 1, 2, 3, 1, 2, 3, 4, 1, 2, 1, 2, 3, 1, 2, 3, 4, 1, 2, 3, 4, 5, 1, 2, 1, 2, 3, 1, 2, 1, 2, 3, 1, 2, 3, 4, 1, 2 (list; graph; listen)
OFFSET

1,3

COMMENT

Also a triangle collected from the Catalan generating tree, with row n containing A000108(n) terms: 1; 1,2; 1,2,1,2,3; 1,2,1,2,3,1,2,1,2,3,1,2,3,4; and ending with n. Rows converge towards A007001, the "last" row.

LINKS

C. Banderier, A. Denise, P. Flajolet, M. Bousquet-Melou et al., Generating Functions for Generating Trees, Discrete Mathematics 246(1-3), March 2002, pp. 29-55.

A. Karttunen, Notes concerning A080237-tree and related sequences.

R. P. Stanley, Catalan addendum. See the interpretation (www, "Vertices of height n-1 of the tree T ...").

FORMULA

It seems that sum(k=1, n, a(k))= C*n*log(log(n)) + O(n*log(log(n))) with C=0.6....

a(n) = A007814(A014486(n)) (i.e. number of trailing zeros in A063171(n)).

EXAMPLE

Sequence begins: 1,(1,2),(1,2),(1,2,3), ...where runs are between 2 parentheses . 5-th run is (1,2) since a(4)=1 and sequence continues: 1,1,2,1,2,1,2,3,1,2....

CROSSREFS

Cf. A000002. Positions of ones: A085223. The first occurrence of each n is at A014138(n). See A085178.

Sequence in context: A134156 A067815 A133780 this_sequence A136109 A105265 A061394

Adjacent sequences: A080234 A080235 A080236 this_sequence A080238 A080239 A080240

KEYWORD

nonn,tabf

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Mar 18 2003

EXTENSIONS

Additional comments from Antti Karttunen (his-firstname.his-surname(AT)gmail.com), Jun 17 2003.

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Last modified July 24 12:00 EDT 2008. Contains 142294 sequences.


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