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A252744
a(n) = A252742(A163511(n)).
6
0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1
OFFSET
0
COMMENTS
a(n) is 1 if the n-th node in A163511 (starting offset 0) has a pair of children where the left child is smaller than the right child, otherwise zero.
LINKS
FORMULA
a(n) = A252742(A163511(n)).
a(n) = A252743(A054429(n)). [The tree is a mirror image of the tree of A252743.]
EXAMPLE
The first six levels of the binary tree (compare also to the illustration given at A163511):
0
|
0
............../ \..............
1 0
....../ \...... ....../ \......
1 1 1 0
/ \ / \ / \ / \
/ \ / \ / \ / \
1 1 1 0 1 1 1 0
/ \ / \ / \ / \ / \ / \ / \ / \
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0
For n=0, the corresponding node in A163511(0) is 1, which has just one child 2, thus we set a(0) = 0.
For n=1, the corresponding node in A163511(1) is 2, which has children 4 > 3, with left child not less than the right child, thus a(1) = 0.
On the other hand, for node 4, in position 3, with its children 8 < 9, thus a(2) = 1. But for node 3, in position 4, with its children 6 > 5, we set a(4) = 0.
PROG
(Scheme) (define (A252744 n) (A252742 (A163511 n)))
CROSSREFS
Permutations: A252742, A252743.
Cf. A252745 (number of ones) and A252746 (number of zeros on each level of binary tree).
Sequence in context: A011656 A295309 A353670 * A340373 A043545 A094754
KEYWORD
nonn,tabf
AUTHOR
Antti Karttunen, Dec 21 2014
STATUS
approved