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%I #10 Feb 15 2015 16:33:37
%S 0,1,2,3,4,5,6,7,8,9,1,11,252,494,252,525,272,272,252,171,2,252,22,
%T 161,696,525,494,999,252,232,3,434,2112,33,272,525,252,111,494,585,4,
%U 656,252,989,44,585,414,141,2112,343,5,969,676,212,27972,55,616,171,232
%N Obtain m by omitting trailing zeros from n (cf. A004151); a(n) = smallest multiple k*m which is a palindrome.
%C Every positive integer is a factor of a palindrome, unless it is a multiple of 10 (D. G. Radcliffe, see links).
%C Every integer n has a multiple of the form 99...9900...00. To see that n has a multiple that's a palindrome (allowing 0's on the left) with even digits, let 9n divide 99...9900...00; then n divides 22...2200...00. - _Dean Hickerson_, Jun 29 2001
%H P. De Geest, <a href="http://www.worldofnumbers.com/em36.htm">Smallest multipliers to make a number palindromic</a>.
%e For n = 30 we have m = 3, 1*m = 3 is a palindrome, so a(30) = 3. For n = m = 12 the smallest palindromic multiple is 21*m = 252, so a(12) = 252.
%o (ARIBAS): stop := 200000; for n := 0 to maxarg do k := 1; test := true; while test and k < stop do mp := omit_trailzeros(n)*k; if test := mp <> int_reverse(mp) then inc(k); end; end; if k < stop then write(mp," "); else write(-1," "); end; end;
%Y Cf. A050782, A062293, A061915, A061916. Values of k are given in A061906.
%K base,easy,nonn
%O 0,3
%A _Klaus Brockhaus_, Jun 25 2001
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