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A295894
Binary weight of the contents of node n in Doudna-tree (A005940).
4
1, 1, 2, 1, 2, 2, 2, 1, 3, 2, 4, 2, 3, 2, 4, 1, 3, 3, 3, 2, 3, 4, 4, 2, 3, 3, 4, 2, 6, 4, 3, 1, 3, 3, 2, 3, 5, 3, 6, 2, 4, 3, 4, 4, 6, 4, 4, 2, 5, 3, 4, 3, 6, 4, 4, 2, 6, 6, 7, 4, 5, 3, 6, 1, 2, 3, 4, 3, 2, 2, 4, 3, 5, 5, 4, 3, 4, 6, 6, 2, 5, 4, 6, 3, 3, 4, 6, 4, 5, 6, 4, 4, 7, 4, 5, 2, 4, 5, 6, 3, 6, 4, 6, 3, 7, 6, 8, 4, 5, 4, 5, 2, 6, 6, 3, 6, 7, 7, 5, 4, 5
OFFSET
0,3
FORMULA
a(n) = A000120(A005940(1+n)).
a(2n+1) = a(n).
A000035(a(n)) = A295895(n).
EXAMPLE
The first six levels of the binary tree (compare also to the illustration given at A005940):
1
|
1
............../ \..............
2 1
....../ \...... ....../ \......
2 2 2 1
/ \ / \ / \ / \
/ \ / \ / \ / \
3 2 4 2 3 2 4 1
/ \ / \ / \ / \ / \ / \ / \ / \
3 3 3 2 3 4 4 2 3 3 4 2 6 4 3 1
For n=0, the corresponding node in A005940(0+1) is 1, in binary also 1, thus a(0) = A000120(1) = 1.
For n=1, the corresponding node in A005940(1+1) is 2, in binary "10", thus a(1) = A000120(2) = 1.
For n=2, the corresponding node in A005940(1+2) is 3, in binary "11", thus a(2) = A000120(3) = 2.
For n=3, the corresponding node in A005940(1+3) is 4, in binary "100", thus a(3) = A000120(4) = 1.
PROG
(Scheme) (define (A295894 n) (A000120 (A005940 (+ 1 n))))
CROSSREFS
Cf. A000225 (the positions of ones).
Sequence in context: A060764 A105149 A355748 * A068307 A363721 A158946
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 30 2017
STATUS
approved