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A023416 Number of 0's in binary expansion of n. 154
1, 0, 1, 0, 2, 1, 1, 0, 3, 2, 2, 1, 2, 1, 1, 0, 4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0, 5, 4, 4, 3, 4, 3, 3, 2, 4, 3, 3, 2, 3, 2, 2, 1, 4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0, 6, 5, 5, 4, 5, 4, 4, 3, 5, 4, 4, 3, 4, 3, 3, 2, 5, 4, 4, 3, 4, 3, 3, 2, 4, 3, 3, 2, 3, 2, 2, 1, 5, 4, 4, 3, 4, 3, 3, 2, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Another version (A080791) has a(0) = 0.

REFERENCES

Vladimir Shevelev, The number of permutations with prescribed up-down structure as a function of two variables, INTEGERS, 12 (2012), #A1. - From N. J. A. Sloane, Feb 07 2013

LINKS

N. J. A. Sloane, Table of n, a(n) for n = 0..10000

R. Stephan, Some divide-and-conquer sequences ...

R. Stephan, Table of generating functions

R. Stephan, Divide-and-conquer generating functions. I. Elementary sequences

Index entries for sequences related to binary expansion of n

FORMULA

a(n) = 1, if n = 0; 0, if n = 1; a(n/2)+1 if n even; a((n-1)/2) if n odd.

a(n) = 1 - (n mod 2) + a(floor(n/2)) - Marc LeBrun, Jul 12 2001

G.f.: 1 + 1/(1-x) * Sum(k>=0, x^(2^(k+1))/(1+x^2^k)). - Ralf Stephan, Apr 15 2002

a(n) = A070939(n)-A000120(n).

a(n) = A008687(n+1) - 1.

a(n) = A000120(A035327(n)).

Contribution from Hieronymus Fischer, Jun 12 2012: (Start)

a(n) = m + 1 + sum_{j=1..m+1} (floor(n/2^j) - floor(n/2^j + 1/2)), where m=floor(log_2(n)).

General formulas for the number of digits <= d in the base p representation n, where 0 <= d < p.

a(n) = m + 1 + sum_{j=1..m+1} (floor(n/p^j) - floor(n/p^j + (p-d-1)/p)), where m=floor(log_p(n)).

G.f.: g(x) = 1 + (1/(1-x))*sum_{j>=0} (1-x^(d*p^j))*x^p^j) + (1-x^p^j)*x^p^(j+1)/(1-x^p^(j+1)). (End)

MAPLE

A023416 := proc(n)

    if n = 0 then

        1;

    else

        add(1-e, e=convert(n, base, 2)) ;

    end if;

end proc: # R. J. Mathar, Jul 21 2012

MATHEMATICA

Table[ Count[ IntegerDigits[n, 2], 0], {n, 0, 100} ]

DigitCount[Range[0, 110], 2, 0] (* Harvey P. Dale, Jan 10 2013 *)

PROG

(Haskell)

a023416 0 = 1

a023416 1 = 0

a023416 n = a023416 n' + 1 - m where (n', m) = divMod n 2

a023416_list = 1 : c [0] where c (z:zs) = z : c (zs ++ [z+1, z])

-- Reinhard Zumkeller, Feb 19 2012, Jun 16 2011, Mar 07 2011

(PARI) a(n)=n=binary(n); sum(i=1, #n, !n[i]) \\ Charles R Greathouse IV, Jun 10 2011

(PARI) a(n)=#binary(n)-hammingweight(n) \\ Charles R Greathouse IV, Nov 20 2012

CROSSREFS

The basic sequences concerning the binary expansion of n are A000120, A000788, A000069, A001969, A023416, A059015, A070939, A083652. Partial sums see A059015.

With initial zero and shifted right, same as A080791.

Cf. A055641 (for base 10).

Sequence in context: A116382 A050606 * A080791 A124748 A161225 A174980

Adjacent sequences:  A023413 A023414 A023415 * A023417 A023418 A023419

KEYWORD

nonn,nice,easy,base,changed

AUTHOR

David W. Wilson

STATUS

approved

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Last modified May 20 02:57 EDT 2013. Contains 225446 sequences.