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%I #13 Nov 04 2023 14:01:16
%S 1109111,110091011,111091111,10109901101,10110911101,11000910011,
%T 11010911011,11100910111,1010099010101,1010109110101,1011099011101,
%U 1100009100011,1101009101011,1110009100111,100109990011001
%N Numbers k such that k^2 is a palindromic square with an asymmetric root.
%C With 'asymmetric' is meant almost palindromic with a 'core' (pseudo-palindromic). The core '09' when transformed into '1n' (n=-1) makes the base number palindromic. E.g., 1109111 is in fact 11_09_111 -> 11_(10-1)_111 -> 11_1n_111 -> 111n111 and palindromic. Similarly core 099 becomes 10n, core 0999 becomes 100n, etc.
%D M. Keith, "Classification and Enumeration of Palindromic Squares," Journal of Recreational Mathematics, 22:2, pp. 124-132, 1990.
%H Hugo Pfoertner, <a href="/A060087/b060087.txt">Table of n, a(n) for n = 1..10032</a>
%H Patrick De Geest, <a href="http://www.worldofnumbers.com/subsquar.htm">Subsets of Palindromic Squares</a>
%H IBM Research Ponder This, <a href="https://research.ibm.com/haifa/ponderthis/challenges/October2023.html">Non-palindromic numbers with palindromic squares</a>, October 2023 - Challenge.
%Y Cf. A060088, A007573, A059744, A059745.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, Feb 15 2001
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