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A048344 a(n) * a(n)_reversed is a palindrome (and a(n) is not palindromic).

%I A048344 #30 Aug 27 2025 03:56:29
%S A048344 12,21,102,112,122,201,211,221,1002,1011,1012,1021,1022,1101,1102,
%T A048344 1112,1121,1201,1202,1211,2001,2011,2012,2021,2101,2102,2111,2201,
%U A048344 10002,10011,10012,10021,10022,10102,10111,10112,10121,10202,10211,11001
%N A048344 a(n) * a(n)_reversed is a palindrome (and a(n) is not palindromic).
%C A048344 Does any term in this sequence have any digit greater than 2? - _Harvey P. Dale_, Nov 05 2011
%H A048344 Reinhard Zumkeller, <a href="/A048344/b048344.txt">Table of n, a(n) for n = 1..1000</a>
%H A048344 Patrick De Geest, <a href="https://www.worldofnumbers.com/reversal.htm">Palindromic Products of Non Palindromic Integers and their Reversals </a>
%e A048344 E.g. 10021 * 12001 = 120262021 is a palindrome.
%t A048344 palQ[n_]:=Module[{idn=IntegerDigits[n],ridn,idn2},ridn=Reverse[idn]; idn2 = IntegerDigits[ n FromDigits[ridn]];idn!=ridn&&idn2==Reverse[idn2]]; Select[ Range[11100],palQ] (* _Harvey P. Dale_, Nov 05 2011 *)
%t A048344 Select[Range[12000],!PalindromeQ[#]&&PalindromeQ[# IntegerReverse[#]]&] (* _Harvey P. Dale_, Jul 10 2023 *)
%o A048344 (Haskell)
%o A048344 a048344 n = a048344_list !! (n-1)
%o A048344 a048344_list = filter f a029742_list where
%o A048344    f x = a136522 (x * a004086 x) == 1
%o A048344 -- _Reinhard Zumkeller_, Oct 09 2011
%o A048344 (Python)
%o A048344 A048344_list = []
%o A048344 for n in range(1,10**5):
%o A048344     s = str(n)
%o A048344     s2 = str(n)[::-1]
%o A048344     if s != s2:
%o A048344         s3 = str(n*int(s2))
%o A048344         if s3 == s3[::-1]:
%o A048344             A048344_list.append(n) # _Chai Wah Wu_, Sep 08 2014
%Y A048344 Cf. A048343.
%Y A048344 Cf. A004086, A136522, A029742.
%K A048344 nonn,base,nice,changed
%O A048344 1,1
%A A048344 _Patrick De Geest_, Feb 15 1999
%E A048344 Offset corrected by _Reinhard Zumkeller_, Oct 09 2011