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A126304 a(n) = number of nodes with nonzero even distance to the root in the n-th plane general tree encoded by A014486(n). 4
0, 0, 0, 1, 0, 1, 1, 2, 1, 0, 1, 1, 2, 1, 1, 2, 2, 3, 2, 1, 2, 1, 2, 0, 1, 1, 2, 1, 1, 2, 2, 3, 2, 1, 2, 1, 2, 1, 2, 2, 3, 2, 2, 3, 3, 4, 3, 2, 3, 2, 3, 1, 2, 2, 3, 2, 1, 2, 1, 2, 2, 3, 2, 3, 2, 0, 1, 1, 2, 1, 1, 2, 2, 3, 2, 1, 2, 1, 2, 1, 2, 2, 3, 2, 2, 3, 3, 4, 3, 2, 3, 2, 3, 1, 2, 2, 3, 2, 1, 2, 1, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,8

LINKS

Table of n, a(n) for n=0..101.

EXAMPLE

A014486(27) = 696 (1010111000 in binary), encodes the following general plane tree, where the root is marked with * and nodes with even or odd distance to root with 'e's and 'o's, respectively.

.......o

.......|

.......e

.......|

...o.o.o

....\|/.

.....*..

there is one node marked with 'e', thus a(27)=1.

PROG

(Scheme:) (define (A126304 n) (*A126304 (A014486->parenthesization (A014486 n))))

(define (*A126304 s) (cond ((null? s) 0) (else (apply + (map *A126303 s)))))

CROSSREFS

a(n) = A126305(n)-1. Cf. A126303. Scheme-function A014486->parenthesization given in A014486.

Sequence in context: A293461 A255482 A204172 * A280522 A324796 A049455

Adjacent sequences:  A126301 A126302 A126303 * A126305 A126306 A126307

KEYWORD

nonn

AUTHOR

Antti Karttunen, Jan 02 2007

STATUS

approved

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Last modified April 17 14:32 EDT 2021. Contains 343063 sequences. (Running on oeis4.)