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%I #40 May 24 2021 00:33:47
%S 1,2,101,174,211,249,257,1822,2070,20795,9531980,17880587,215198695,
%T 1702002467,167526192487,196759830168,2036493584526,17476134422427,
%U 82406037714600,170438376135142,181002188703854,189344689666188,213031868452710,10020895012660701,17108271682888342
%N Numbers m such that m-th centered triangular number is a palindrome.
%C Computed by _Robert G. Wilson v_.
%C a(18) > 2581988897472. - _Donovan Johnson_, Sep 29 2011
%C a(31) > 81649658092772603272. - _Patrick De Geest_, May 23 2021
%H Patrick De Geest, <a href="/A195903/b195903.txt">Table of n, a(n) for n = 1..30</a>
%H Terry Trotter, <a href="http://trottermath.net/polygonal-numbers/">Polygonal numbers</a> [numbers >=920 on this page were incorrect when accessed Sep 25 2011] [Warning: As of March 2018 this site appears to have been hacked. Proceed with great caution. The original content should be retrieved from the Wayback machine and added here. - _N. J. A. Sloane_, Mar 29 2018]
%H Terry Trotter, <a href="https://web.archive.org/web/20160420101547/http://trottermath.net/polygonal-numbers/">Polygonal Numbers</a>, from the Wayback machine
%H Patrick De Geest, <a href="http://www.worldofnumbers.com/centered.htm">Palindromic Centered Polygonal Numbers</a>
%Y Cf. A005448, A162703.
%K nonn,base
%O 1,2
%A _Kausthub Gudipati_, Sep 25 2011
%E a(14) from _D. S. McNeil_, Sep 26 2011
%E a(15)-a(17) from _Donovan Johnson_, Sep 29 2011
%E a(18)-a(30) from _Patrick De Geest_, May 23 2021