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A062279 Smallest multiple k*n of n which is a palindrome or becomes a palindrome when 0's are added on the left (e.g. 10 becomes 010 which is a palindrome). 5

%I

%S 0,1,2,3,4,5,6,7,8,9,10,11,60,494,70,30,80,272,90,171,20,252,22,161,

%T 600,50,494,999,252,232,30,434,800,33,272,70,252,111,494,585,40,656,

%U 252,989,44,90,414,141,2112,343,50,969,676,212,9990,55,616,171,232,767

%N Smallest multiple k*n of n which is a palindrome or becomes a palindrome when 0's are added on the left (e.g. 10 becomes 010 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).

%H Reinhard Zumkeller, <a href="/A062279/b062279.txt">Table of n, a(n) for n = 0..1000</a>

%H P. De Geest, <a href="http://www.worldofnumbers.com/em36.htm">Smallest multipliers to make a number palindromic</a>.

%F A136522(A004151(a(n))) = 1. - _Reinhard Zumkeller_, May 06 2013

%e a(13) = 494 is the smallest multiple of 13 which is a palindrome.

%o (ARIBAS): maxarg := 60; stop := 200000; for n := 0 to maxarg do k := 1; test := true; while test and k < stop do m := omit_trailzeros(n*k); if test := m <> int_reverse(m) then inc(k); end; end; if k < stop then write(n*k," "); else write(-1," "); end; end;

%o (Haskell)

%o a062279 0 = 0

%o a062279 n = until ((== 1) . a136522 . a004151) (+ n) n

%o -- _Reinhard Zumkeller_, May 06 2013

%Y Cf. A050782, A062293. Values of k are given in A061674.

%Y Cf. A141709.

%K nonn,base,easy,nice

%O 0,3

%A _Amarnath Murthy_, Jun 17 2001

%E Corrected and extended by Larry Reeves (larryr(AT)acm.org) and _Klaus Brockhaus_, Jun 18 2001

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Last modified April 20 14:27 EDT 2019. Contains 322310 sequences. (Running on oeis4.)