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A037857 Sum{d(i)-d(i-1): d(i)>d(i-1), i=1,...,m}, where Sum{d(i)*7^i: i=0,1,...,m} is base 7 representation of n. 3
0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 2, 1, 0, 0, 0, 0, 0, 3, 2, 1, 0, 0, 0, 0, 4, 3, 2, 1, 0, 0, 0, 5, 4, 3, 2, 1, 0, 0, 6, 5, 4, 3, 2, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 2, 1, 0, 0, 0, 0, 0, 3, 2, 1, 0, 0, 0, 0, 4, 3, 2, 1, 0, 0, 0, 5, 4, 3, 2, 1, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,14

COMMENTS

This is the base-7 down-variation sequence; see A297330. - Clark Kimberling, Jan 18 2017

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..10000

MAPLE

A037857 := proc(n)

    a := 0 ;

    dgs := convert(n, base, 7);

    for i from 2 to nops(dgs) do

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

            a := a+op(i, dgs)-op(i-1, dgs) ;

        end if;

    end do:

    a ;

end proc: # R. J. Mathar, Oct 19 2015

CROSSREFS

g[n_, b_] := Differences[IntegerDigits[n, b]]; b = 7; z = 120;

Table[-Total[Select[g[n, b], # < 0 &]], {n, 1, z}];  (*A037857*)

Table[Total[Select[g[n, b], # > 0 &]], {n, 1, z}];   (*A037848*)

Sequence in context: A173677 A219480 A277627 * A037875 A057764 A010108

Adjacent sequences:  A037854 A037855 A037856 * A037858 A037859 A037860

KEYWORD

nonn,base

AUTHOR

Clark Kimberling

EXTENSIONS

Definition swapped with A037848. - R. J. Mathar, Oct 19 2015

Updated by Clark Kimberling, Jan 19 2018

STATUS

approved

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Last modified September 15 16:40 EDT 2019. Contains 327078 sequences. (Running on oeis4.)