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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A037862 a(n)=(number of digits <=1)-(number of digits >1) in base 3 representation of n. 1
1, -1, 2, 2, 0, 0, 0, -2, 3, 3, 1, 3, 3, 1, 1, 1, -1, 1, 1, -1, 1, 1, -1, -1, -1, -3, 4, 4, 2, 4, 4, 2, 2, 2, 0, 4, 4, 2, 4, 4, 2, 2, 2, 0, 2, 2, 0, 2, 2, 0, 0, 0, -2, 2, 2, 0, 2, 2, 0, 0, 0, -2, 2, 2, 0, 2, 2, 0, 0, 0, -2, 0, 0, -2, 0, 0, -2, -2, -2, -4, 5, 5, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..83.

MAPLE

A037862 := proc(n)

    a := 0 ;

    dgs := convert(n, base, 3);

    for i from 1 to nops(dgs) do

        if op(i, dgs)<=1 then

            a := a+1 ;

        else

            a := a-1 ;

        end if;

    end do:

    a ;

end proc: # R. J. Mathar, Oct 16 2015

MATHEMATICA

b3d[n_]:=Module[{idn=IntegerDigits[n, 3]}, Count[idn, _?(#<2&)]-Count[idn, _?(#>1&)]]; Array[b3d, 90] (* Harvey P. Dale, Nov 08 2011 *)

CROSSREFS

Sequence in context: A054978 A129438 A125096 * A285244 A263148 A230819

Adjacent sequences:  A037859 A037860 A037861 * A037863 A037864 A037865

KEYWORD

base,sign

AUTHOR

Clark Kimberling

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 October 15 22:25 EDT 2019. Contains 328038 sequences. (Running on oeis4.)