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A057515
Number of separate "mountains" in mountain ranges encoded by A014486, number of bottom branches (trunks) in the corresponding rooted plane trees, i.e., the degree of the root node.
32
0, 1, 2, 1, 3, 2, 2, 1, 1, 4, 3, 3, 2, 2, 3, 2, 2, 1, 1, 2, 1, 1, 1, 5, 4, 4, 3, 3, 4, 3, 3, 2, 2, 3, 2, 2, 2, 4, 3, 3, 2, 2, 3, 2, 2, 1, 1, 2, 1, 1, 1, 3, 2, 2, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 1, 6, 5, 5, 4, 4, 5, 4, 4, 3, 3, 4, 3, 3, 3, 5, 4, 4, 3, 3, 4, 3, 3, 2, 2, 3, 2, 2, 2, 4, 3, 3, 2, 2, 3, 2, 2, 2, 3, 2, 2
OFFSET
0,3
COMMENTS
This sequence is produced when the function 'length' (present in programming languages like Lisp, Scheme, Prolog and Haskell) acts on symbolless S-expressions encoded by A014486/A063171.
LINKS
A. Karttunen, Gatomorphisms (Includes the complete Scheme program for computing this sequence)
CROSSREFS
a(n) gives the first digit of A071153(n).
Sequence in context: A023595 A372516 A177718 * A300712 A282463 A265337
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 03 2000
STATUS
approved