

A107478


Slowest increasing sequence where: 1) a(n) cannot contain any "0" and 2) a(n) must contain one digit of the product of the digits of a(n1).


0



1, 11, 12, 21, 22, 24, 28, 31, 32, 36, 38, 41, 42, 48, 52, 61, 62, 71, 72, 74, 78, 85, 94, 96, 114, 124, 128, 129, 131, 132, 136, 137, 138, 141, 142, 148, 152, 153, 154, 162, 163, 164, 172, 173
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OFFSET

1,2


LINKS

Table of n, a(n) for n=1..44.


EXAMPLE

After a(n)=1 we cannot have 10 (presence of a "0"), thus 11; product of 1x1 is 1, so next integer must contain a "1", thus 12; product 1x2=2, so next integer must contain a "2", thus 21 (20 not allowed), etc.


CROSSREFS

Sequence in context: A109372 A066686 A125887 * A153146 A132359 A131363
Adjacent sequences: A107475 A107476 A107477 * A107479 A107480 A107481


KEYWORD

base,easy,nonn


AUTHOR

Eric Angelini, Jun 09 2005


STATUS

approved



