

A100922


n appears A000120(n) times (appearances equal number of 1bits).


4



1, 2, 3, 3, 4, 5, 5, 6, 6, 7, 7, 7, 8, 9, 9, 10, 10, 11, 11, 11, 12, 12, 13, 13, 13, 14, 14, 14, 15, 15, 15, 15, 16, 17, 17, 18, 18, 19, 19, 19, 20, 20, 21, 21, 21, 22, 22, 22, 23, 23, 23, 23, 24, 24, 25, 25, 25, 26, 26, 26, 27, 27, 27, 27, 28, 28, 28, 29, 29, 29, 29, 30, 30, 30
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OFFSET

0,2


COMMENTS

Clearly every positive integer appears at least once in this sequence.


LINKS



FORMULA

Sum_{n>=1} (1)^(n+1)/a(n) = Sum_{n>=1} (1)^(n+1)/A000069(n) = 0.67968268... .  Amiram Eldar, Feb 18 2024


EXAMPLE

The binary representation of 16 is 10000, which has one 1bit (and four 0bits), hence 16 appears once in this sequence (and four times in A100921).


MATHEMATICA

Table[Table[n, DigitCount[n, 2, 1]], {n, 30}]//Flatten (* Harvey P. Dale, Aug 31 2017 *)


PROG



CROSSREFS



KEYWORD

base,easy,nonn


AUTHOR



STATUS

approved



