%I #10 Dec 03 2018 13:04:07
%S 11,22,33,44,55,66,77,88,99,100,1111,1212,1131,1414,555,1616,1717,
%T 1188,1919,200,2121,2222,322,2424,225,2262,2727,2828,2929,300,1333,
%U 3232,3333,3434,3535,3636,333,3838,3393,400,4141,4242,344,4444,4455,644,4747,4848
%N Smallest multiple of n other than n using only the digits of n (no limit on frequency).
%C a(k) = 10k if k contains a zero. a(n) <= (10^d +1)*n where d is the number of digits in n. There are some patterns in which every digit is used exactly as many times as it occurs in n. (A008918 and A001232). (1) a(2178) = 8712, a(21978) = 87912, a(219978) = 879912, etc... with a(n)/n = 4. A derived pattern is a(21782178) = 87128712, a(217821782178) = 871287128712 etc. (2) a(1089) = 9801, a(10989) = 98901, a(109989)= 989901,... with a(n)/n = 9. More patterns can be derived on similar lines.
%H Ray Chandler, <a href="/A078273/b078273.txt">Table of n, a(n) for n = 1..10000</a>
%e a(30) = 300, a(2178) = 8712, a(1089) = 9801.
%t smn[n_]:=Module[{k=2},While[!SubsetQ[IntegerDigits[n],IntegerDigits[ k*n]], k++];k*n]; Array[smn,50] (* _Harvey P. Dale_, Dec 03 2018 *)
%Y Cf. A008918, A001232.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_, Nov 24 2002
%E Corrected and extended by _Sean A. Irvine_, Mar 09 2010
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