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A371571
Irregular triangle read by rows: row n lists the 1-based positions (starting from the left) of zeros in the binary expansion of n, or 0 if the binary expansion of n contains only ones.
18
1, 0, 2, 0, 2, 3, 2, 3, 0, 2, 3, 4, 2, 3, 2, 4, 2, 3, 4, 3, 4, 0, 2, 3, 4, 5, 2, 3, 4, 2, 3, 5, 2, 3, 2, 4, 5, 2, 4, 2, 5, 2, 3, 4, 5, 3, 4, 3, 5, 3, 4, 5, 4, 5, 0, 2, 3, 4, 5, 6, 2, 3, 4, 5, 2, 3, 4, 6, 2, 3, 4, 2, 3, 5, 6, 2, 3, 5, 2, 3, 6, 2, 3, 2, 4, 5, 6
OFFSET
0,3
LINKS
Paolo Xausa, Table of n, a(n) for n = 0..10384 (rows 0..2200 of the triangle, flattened).
EXAMPLE
Triangle begins:
[0] 1;
[1] 0;
[2] 2;
[3] 0;
[4] 2, 3;
[5] 2;
[6] 3;
[7] 0;
[8] 2, 3, 4;
...
Row n = 50 is 3, 4, 6:
binary expansion of 50: 1 1 0 0 1 0
positions of zeros: - - 3 4 - 6
MATHEMATICA
Array[Replace[Flatten[Position[IntegerDigits[#, 2], 0]], {} -> {0}] &, 50, 0]
CROSSREFS
Cf. A359359 (row sums), A371572 (position of ones).
Cf. A368494.
Sequence in context: A285721 A214292 A212184 * A033769 A333636 A074660
KEYWORD
nonn,base,tabf,easy
AUTHOR
Paolo Xausa, Mar 28 2024
STATUS
approved