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%I #35 Jun 21 2015 14:14:16
%S 1,100,10000,1000000,1306449,100000000,130644900,1044000721,
%T 10000000000,12957041241,13064490000,104400072100,1000000000000,
%U 1019072079081,1174279984164,1295704124100,1306449000000,6454272356676,10440007210000
%N Squares whose reverse is a triangular number; trailing zeros are permitted.
%C Suggested by _T. D. Noe_.
%H Giovanni Resta, <a href="/A181412/b181412.txt">Table of n, a(n) for n = 1..73</a> (terms < 10^24)
%e 1306449 is 1143 squared, and its reverse, 9446031, is a triangular number.
%t trnos = Accumulate[Range[300000]]; Select[Range[210000]^2, MemberQ[trnos, FromDigits[Reverse[IntegerDigits[#]]]] &]
%Y Cf. A066702, A001110, A066703, A179889, A066528, A069673.
%K nonn,base
%O 1,2
%A _Harvey P. Dale_, Jan 30 2011
%E a(12)-a(19) from _Donovan Johnson_, Feb 12 2011