A134942 - OEIS

%I #7 Jan 21 2013 12:28:15

%S 1,2,3,4,5,6,7,8,21,23,27,29,32,33,36,39,41,43,44,47,48,49,51,53,54,

%T 56,57,61,62,63,65,67,68,69,71,72,75,76,77,78,79,81,83,84,85,86,87,88,

%U 89,90,91,92,93,94,95,96,97,98,99,121,123,127,129,132,133,136,139,141,143

%N Numbers n such that there exists no number k with k-P(k) = n, where P(k) is the product of digits of k written in base 10.

%C Obviously no number containing a zero digit is in the sequence.

%e For 0 <= p <= 9, p - P(p) = 0, hence 0 is in the sequence.

%e It's easy to see that if p has 2 digits or more the difference p - P(p) has at least 2 digits, hence 1 to 9 are in the sequence.

%K easy,nonn,base

%O 1,2

%A Philippe Lallouet (philip.lallouet(AT)orange.fr), Feb 01 2008