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A196096 Occurrences of '11' in base 3 expansion of n. 2
0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 2, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 2, 3, 2, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 2, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,14

COMMENTS

Occurrences of '11' in A007089(n). This is to base 3 and A007089 as A014081 is to base 2 A007088.

First occurrence of k>0 = 4, 13, 40, 121, 364, ..., = A003462(k). (* Robert G. Wilson v, Sep 27 2011 *)

LINKS

T. D. Noe, Table of n, a(n) for n = 0..1000

EXAMPLE

a(4) = 1 because 4 in base 3 is "11" which has one instance of "11".

a(13) = 2 because the number 13 in base 3 is "111" which has two substrings of "11".

MAPLE

A196096 := proc(n)

        local a, dgs3 ;

        a := 0 ;

        dgs3 := convert(n, base, 3) ;

        for i from 1 to nops(dgs3)-1 do

                if op(i, dgs3)=1 and op(i+1, dgs3)=1 then

                        a := a+1 ;

                end if;

        end do;

        a ;

end proc:

seq(A196096(n), n=0..80) ; # R. J. Mathar, Sep 28 2011

MATHEMATICA

f[n_] := Count[ Partition[ IntegerDigits[ n, 3], 2, 1], {1, 1}]; Array[f, 100, 0] (* Robert G. Wilson v, Sep 27 2011 *)

CROSSREFS

Cf. A007089, A014081.

Sequence in context: A037878 A107652 A186734 * A249344 A067150 A289922

Adjacent sequences:  A196093 A196094 A196095 * A196097 A196098 A196099

KEYWORD

easy,nonn

AUTHOR

Jonathan Vos Post, Sep 27 2011

STATUS

approved

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Last modified January 18 16:27 EST 2020. Contains 331011 sequences. (Running on oeis4.)