login
This site is supported by donations to The OEIS Foundation.

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A143909 A positive integer n is included if the number of digits in the binary representation of n is a multiple of the number of zeros in the binary representation of n. 1
2, 5, 6, 9, 10, 11, 12, 13, 14, 23, 27, 29, 30, 35, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 95, 111, 119, 123, 125, 126, 135, 139, 141, 142, 147, 149, 150, 153, 154, 156, 159, 163, 165, 166, 169, 170, 172, 175, 177 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..63.

FORMULA

{n: A080791(n) | A070939(n)}. - R. J. Mathar, Sep 05 2008

MAPLE

A070939 := proc(n) max(1, 1+floor(ilog2(n))) ; end: A080791 := proc(n) local dgs ; dgs := convert(n, base, 2) ; nops(dgs)-add(i, i=dgs) ; end: isA143909 := proc(n) zs := A080791(n) ; if zs > 0 then if A070939(n) mod zs = 0 then true ; else false ; fi; else false ; fi; end: for n from 1 to 500 do if isA143909(n) then printf("%d, ", n) ; fi; od: # R. J. Mathar, Sep 05 2008

MATHEMATICA

Select[Range[200], DigitCount[ #, 2, 0] > 0 && Mod[Length[IntegerDigits[ #, 2]], DigitCount[ #, 2, 0]] == 0 &] (* Stefan Steinerberger, Sep 05 2008 *)

CROSSREFS

Cf. A096199.

Sequence in context: A244272 A007573 A285663 * A284507 A284492 A224779

Adjacent sequences:  A143906 A143907 A143908 * A143910 A143911 A143912

KEYWORD

base,nonn

AUTHOR

Leroy Quet, Sep 04 2008

EXTENSIONS

More terms from Stefan Steinerberger and R. J. Mathar, Sep 05 2008

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 16 04:05 EST 2019. Contains 330013 sequences. (Running on oeis4.)