login
A037853
Sum{d(i)-d(i-1): d(i)>d(i-1), i=1,...,m}, where Sum{d(i)*3^i: i=0,1,...,m} is base 3 representation of n.
3
0, 0, 1, 0, 0, 2, 1, 0, 1, 1, 1, 1, 0, 0, 2, 1, 0, 2, 2, 2, 2, 1, 1, 2, 1, 0, 1, 1, 1, 2, 1, 1, 3, 2, 1, 1, 1, 1, 1, 0, 0, 2, 1, 0, 2, 2, 2, 2, 1, 1, 2, 1, 0, 2, 2, 2, 3, 2, 2, 4, 3, 2, 2, 2, 2, 2, 1, 1, 3, 2, 1, 2, 2, 2, 2, 1, 1, 2, 1, 0, 1, 1, 1, 2, 1, 1, 3, 2, 1, 2
OFFSET
1,6
COMMENTS
This is the base-3 down-variation sequence; see A297330. - Clark Kimberling, Jan 18 2018
LINKS
MAPLE
A037853 := proc(n)
a := 0 ;
dgs := convert(n, base, 3);
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 16 2015
MATHEMATICA
g[n_, b_] := Differences[IntegerDigits[n, b]]; b = 3; z = 120;
Table[-Total[Select[g[n, b], # < 0 &]], {n, 1, z}]; (*A037853*)
Table[Total[Select[g[n, b], # > 0 &]], {n, 1, z}]; (*A037844*)
(* Clark Kimberling, Jan 18 2018 *)
CROSSREFS
Sequence in context: A258139 A261887 A037871 * A255237 A291954 A375670
KEYWORD
nonn,base
EXTENSIONS
Definition corrected by R. J. Mathar, Oct 16 2015
STATUS
approved