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%I #20 Feb 27 2020 20:40:50
%S 121,10001,10201,36763,1226221,7673767,12467976421,1030507050301,
%T 1120237320211,1225559555221,1234469644321,1334459544331,
%U 100330272033001,100827848728001,101222252222101,103023070320301,121363494363121,134312696213431,10022212521222001
%N Terms in A144719 that are themselves decimal palindromes.
%C Presumed infinite, but it is difficult to find more terms.
%C The earlier claim that this sequence is a subsequence of A046450 was incorrect, as the counterexample of 7673767 =97*79111 shows. The reason is that A046450 checks only concatenations in the natural order of the prime factors, but this sequence here allows for both orders, 97//79111 as well as 79111//97, to be palindromic. - _R. J. Mathar_, Jan 22 2009
%C 3*10^14 < a(19) <= 10022212521222001. - _Donovan Johnson_, Dec 08 2010
%H Giovanni Resta, <a href="/A144766/b144766.txt">Table of n, a(n) for n = 1..41</a>
%F Subsequence of (A144719 INTERSECT A046328). - _R. J. Mathar_, Jan 22 2009
%e 10001 = 73 * 137; 73137 is a palindrome.
%Y Cf. A002113, A046450, A144719.
%K base,hard,nonn
%O 1,1
%A _Reikku Kulon_, Sep 20 2008
%E a(7)-a(18) from _Donovan Johnson_, Dec 08 2010
%E a(19) from _Giovanni Resta_, Aug 31 2018
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