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A037859
Sum{d(i)-d(i-1): d(i)>d(i-1), i=1,...,m}, where Sum{d(i)*9^i: i=0,1,...,m} is base 9 representation of n.
3
0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 2, 1, 0, 0, 0, 0, 0, 0, 0, 3, 2, 1, 0, 0, 0, 0, 0, 0, 4, 3, 2, 1, 0, 0, 0, 0, 0, 5, 4, 3, 2, 1, 0, 0, 0, 0, 6, 5, 4, 3, 2, 1, 0, 0, 0, 7, 6, 5, 4, 3, 2, 1, 0, 0, 8, 7, 6, 5, 4, 3, 2, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
OFFSET
1,18
COMMENTS
This is the base-9 down-variation sequence; see A297330. - Clark Kimberling, Jan 18 2017
LINKS
MAPLE
A037859 := 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+op(i, dgs)-op(i-1, dgs) ;
end if;
end do:
a ;
end proc: # R. J. Mathar, Oct 19 2015
MATHEMATICA
g[n_, b_] := Differences[IntegerDigits[n, b]]; b = 9; z = 120;
Table[-Total[Select[g[n, b], # < 0 &]], {n, 1, z}]; (*A037859*)
Table[Total[Select[g[n, b], # > 0 &]], {n, 1, z}]; (*A037850*)
CROSSREFS
Sequence in context: A289923 A289921 A219482 * A037877 A010109 A304021
KEYWORD
nonn,base
EXTENSIONS
Definition swapped with A037850. - R. J. Mathar, Oct 19 2015
Updated by Clark Kimberling, Jan 19 2018
STATUS
approved