login
A223474
Least positive multiple of n that when written in base 10 has digits in nonincreasing order.
2
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 60, 52, 42, 30, 32, 51, 54, 76, 20, 21, 22, 92, 72, 50, 52, 54, 84, 87, 30, 31, 32, 33, 442, 70, 72, 74, 76, 663, 40, 41, 42, 43, 44, 90, 92, 94, 96, 98, 50, 51, 52, 53, 54, 55, 840, 741, 522, 531, 60, 61, 62, 63, 64, 65, 66, 871, 544, 552, 70, 71, 72, 73, 74, 75, 76, 77, 6552, 553, 80, 81, 82, 83, 84, 85
OFFSET
1,2
COMMENTS
This sequence is well defined (same reasoning as for A079339).
LINKS
EXAMPLE
a(39) = 663 because it is the least multiple of 39 appearing in A009996.
MATHEMATICA
a[n_] := Block[{x=n}, While[0 < Max@Differences@IntegerDigits@x, x += n]; x]; Array[a, 85] (* Giovanni Resta, Mar 26 2013 *)
PROG
(Perl)
sub A223474 {
my $n = shift;
my $a = $n;
while ($a !~ /^9*8*7*6*5*4*3*2*1*0*$/) {
$a += $n;
}
return $a;
}
foreach (1..100) {
print A223474($_), ", ";
}
CROSSREFS
a(n)/n yields sequence A223475.
Cf. A009996.
Sequence in context: A066638 A285769 A219209 * A062279 A088599 A004862
KEYWORD
nonn,base
AUTHOR
Paul Tek, Mar 20 2013
STATUS
approved