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Smallest palindrome ending with n or 0 if n is a multiple of 10.
2

%I #18 Aug 30 2021 17:18:56

%S 1,2,3,4,5,6,7,8,9,0,11,212,313,414,515,616,717,818,919,0,121,22,323,

%T 424,525,626,727,828,929,0,131,232,33,434,535,636,737,838,939,0,141,

%U 242,343,44,545,646,747,848,949,0,151,252,353,454,55,656,757,858,959

%N Smallest palindrome ending with n or 0 if n is a multiple of 10.

%H Chai Wah Wu, <a href="/A347346/b347346.txt">Table of n, a(n) for n = 1..10000</a>

%F If n is not a multiple of 10, then a(n) = A082216(A004086(n)).

%o (Python)

%o def A347346(n):

%o if n % 10 == 0:

%o return 0

%o s = str(n)

%o if s == s[::-1]:

%o return n

%o for i in range(1,len(s)):

%o if s[:-i]== s[-i-1::-1]:

%o return int(s[:-i-1:-1]+s)

%Y Cf. A004086, A082216, A347347.

%K nonn,base,look

%O 1,2

%A _Chai Wah Wu_, Aug 27 2021