login
A037807
Number of i such that d(i) < d(i-1), where Sum_{i=0..m} d(i)*9^i is the 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
OFFSET
1,1
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
KEYWORD
nonn,base
EXTENSIONS
Sign in name corrected by R. J. Mathar, Oct 16 2015
STATUS
approved