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A371572
Irregular triangle read by rows: row n lists the 1-based positions (starting from the left) of ones in the binary expansion of n, with row 0 = 0.
17
0, 1, 1, 1, 2, 1, 1, 3, 1, 2, 1, 2, 3, 1, 1, 4, 1, 3, 1, 3, 4, 1, 2, 1, 2, 4, 1, 2, 3, 1, 2, 3, 4, 1, 1, 5, 1, 4, 1, 4, 5, 1, 3, 1, 3, 5, 1, 3, 4, 1, 3, 4, 5, 1, 2, 1, 2, 5, 1, 2, 4, 1, 2, 4, 5, 1, 2, 3, 1, 2, 3, 5, 1, 2, 3, 4, 1, 2, 3, 4, 5, 1, 1, 6, 1, 5, 1, 5, 6
OFFSET
0,5
LINKS
Paolo Xausa, Table of n, a(n) for n = 0..11944 (rows 0..2200 of the triangle, flattened).
Michael De Vlieger, Plot (x,y) = (n,T(n,k)), n = 1..1024, where T(n,k) represents the k-th term in the n-th row of the irregular triangle, 32X vertical exaggeration.
EXAMPLE
Triangle begins:
[0] 0;
[1] 1;
[2] 1;
[3] 1, 2;
[4] 1;
[5] 1, 3;
[6] 1, 2;
[7] 1, 2, 3;
[8] 1;
...
Row n = 50 is 1, 2, 5:
binary expansion of 50: 1 1 0 0 1 0
positions of ones: 1 2 - - 5 -
MATHEMATICA
Join[{{0}}, Array[Flatten[Position[IntegerDigits[#, 2], 1]] &, 50]]
CROSSREFS
Cf. A230877 (row sums), A371571 (position of zeros).
Cf. A048793.
Sequence in context: A112377 A354521 A277760 * A127704 A307662 A050873
KEYWORD
nonn,base,tabf,easy
AUTHOR
Paolo Xausa, Mar 28 2024
STATUS
approved