%I #22 May 17 2020 11:19:30
%S 1,2,12,12,10,12,21,112,12222,10,11,12,221,112,120,112,102,12222,1102,
%T 20,21,22,1012,120,100,1222,21222,112,1102,120,2201,1120,1122,102,210,
%U 22212,111,1102,10101,120,11111,210,2021,220,122220,1012,1222,1200
%N a(n) is the smallest positive multiple of n whose decimal digits are all 0, 1 or 2.
%H David A. Corneth, <a href="/A181060/b181060.txt">Table of n, a(n) for n = 1..10000</a>
%H Inspired by Project Euler, Problem 303: <a href="http://projecteuler.net/index.php?section=problems&id=303">Multiples with small digits</a>.
%e a(9)=12222 because 12222 is the smallest multiple of 9 whose decimal digits are all 0, 1 or 2.
%t With[{pms=Rest[Flatten[FromDigits/@Tuples[{0,1,2},6]]]},Table[ SelectFirst[ pms, Divisible[ #,n]&],{n,50}]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Aug 24 2017 *)
%o (PARI) a(n) = my(k=1); while(vecmax(digits(k*n))>2, k++); k*n; \\ _Michel Marcus_, May 17 2020
%Y a(n)/n yields sequence A181061.
%K base,easy,nonn
%O 1,2
%A _Herman Beeksma_, Oct 01 2010
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