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A341910 Lexicographically earliest sequence of distinct nonnegative integers such that for any n >= 0, the number of runs in the binary expansion of n equals the number of ones in the binary expansion of a(n). 2
0, 1, 3, 2, 5, 7, 6, 4, 9, 11, 15, 13, 10, 14, 12, 8, 17, 19, 23, 21, 27, 31, 29, 22, 18, 25, 30, 26, 20, 28, 24, 16, 33, 35, 39, 37, 43, 47, 45, 38, 46, 55, 63, 59, 51, 61, 53, 41, 34, 42, 54, 44, 57, 62, 58, 49, 36, 50, 60, 52, 40, 56, 48, 32, 65, 67, 71, 69 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
This sequence is a permutation of the nonnegative integers with inverse A341911.
Apparently, A037481 corresponds to the fixed points of this sequence.
LINKS
Rémy Sigrist, Colored scatterplot of the first 2^16 terms (where the color is function of A005811(n))
FORMULA
A005811(n) = A000120(a(n)).
a(n) < 2^k for any n < 2^k.
EXAMPLE
The first terms, in decimal and in binary, are:
n a(n) bin(n) bin(a(n))
-- ---- ------- ---------
0 0 0 0
1 1 1 1
2 3 10 11
3 2 11 10
4 5 100 101
5 7 101 111
6 6 110 110
7 4 111 100
8 9 1000 1001
9 11 1001 1011
10 15 1010 1111
MATHEMATICA
Block[{a = {0}, k}, Do[k = 1; While[Nand[FreeQ[a, k], DigitCount[k, 2, 1] == #], k++] &@ Length[Split@ IntegerDigits[i, 2]]; AppendTo[a, k], {i, 67}]; a] (* Michael De Vlieger, Feb 24 2021 *)
PROG
(PARI) See Links section.
CROSSREFS
Sequence in context: A108918 A316472 A360959 * A341915 A371975 A082334
KEYWORD
nonn,look,base
AUTHOR
Rémy Sigrist, Feb 23 2021
STATUS
approved

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Last modified June 6 08:45 EDT 2024. Contains 373119 sequences. (Running on oeis4.)