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A037807 Number of i such that d(i)<d(i-1), where Sum{d(i)*9^i: i=0,1,...,m} is base 9 representation of n. 2
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..90.

MAPLE

A037807 := proc(n)

    a := 0 ;

    dgs := convert(n, base, 9);

    for i from 2 to nops(dgs) do

        if op(i, dgs)<op(i-1, dgs) then

            a := a+1 ;

        end if;

    end do:

    a ;

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

CROSSREFS

Cf. A037824.

Sequence in context: A277155 A277159 A011724 * A037817 A297039 A239705

Adjacent sequences:  A037804 A037805 A037806 * A037808 A037809 A037810

KEYWORD

nonn,base

AUTHOR

Clark Kimberling

EXTENSIONS

Sign in name corrected. - R. J. Mathar, Oct 16 2015

STATUS

approved

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Last modified June 15 08:52 EDT 2021. Contains 345048 sequences. (Running on oeis4.)