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%I A066703 #33 Apr 13 2019 22:13:03
%S A066703 0,1,9446031,1270004401,14214075921,1809702709101,4614899724711,
%T A066703 6766532724546,52657436563056,98855178542676,520454948099628321,
%U A066703 467756399278821844071,40441102744430519189191
%N A066703 Triangular numbers whose reverse is a square with the same number of digits.
%C A066703 The sequence of corresponding squares is A066702. - _Robert G. Wilson v_, Jan 31 2011
%C A066703 a(14) > 2*10^24. - _Giovanni Resta_, Jun 20 2015
%e A066703 9446031 is triangular and 1306449 is a square.
%t A066703 lst = {0}; For[i=1, i<10^6, i++, t=i(i+1)/2; r=FromDigits@ Reverse@ IntegerDigits@ t; If[ Mod[t, 10] > 0 && IntegerQ@ Sqrt@ r, AppendTo[lst, t]; Print@ lst]]
%Y A066703 See A179889 for another version. Cf. A066702, A069673.
%K A066703 base,nonn,more
%O A066703 1,3
%A A066703 _Erich Friedman_, Jan 14 2002
%E A066703 More terms from _Jason Earls_ and the author, Jan 15 2002
%E A066703 Offset and definition modified at the suggestion of _Harvey P. Dale_, Jan 30 2011
%E A066703 a(11) from _Donovan Johnson_, Jan 31 2011
%E A066703 a(12)-a(13) from _Giovanni Resta_, Jun 20 2015

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