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A037864 a(n)=(number of digits <=2)-(number of digits >2) in base 5 representation of n. 1
1, 1, -1, -1, 2, 2, 2, 0, 0, 2, 2, 2, 0, 0, 0, 0, 0, -2, -2, 0, 0, 0, -2, -2, 3, 3, 3, 1, 1, 3, 3, 3, 1, 1, 3, 3, 3, 1, 1, 1, 1, 1, -1, -1, 1, 1, 1, -1, -1, 3, 3, 3, 1, 1, 3, 3, 3, 1, 1, 3, 3, 3, 1, 1, 1, 1, 1, -1, -1, 1, 1, 1, -1, -1, 1, 1, 1, -1, -1, 1, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Table of n, a(n) for n=0..81.

MAPLE

A037864 := proc(n)

    a := 0 ;

    dgs := convert(n, base, 5);

    for i from 1 to nops(dgs) do

        if op(i, dgs)<=2 then

            a := a+1 ;

        else

            a := a-1 ;

        end if;

    end do:

    a ;

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

MATHEMATICA

nd5[n_]:=Module[{idn5=IntegerDigits[n, 5], a}, a=Count[idn5, _?(#<=2&)]; 2a-Length[idn5]]; Array[nd5, 90] (* Harvey P. Dale, Oct 13 2011 *)

CROSSREFS

Sequence in context: A004541 A178045 A321300 * A285635 A181674 A181676

Adjacent sequences:  A037861 A037862 A037863 * A037865 A037866 A037867

KEYWORD

base,sign

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified October 23 17:17 EDT 2019. Contains 328373 sequences. (Running on oeis4.)