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Search: id:A066703
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| A066703 |
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Triangular numbers whose reverse is a square. |
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+0
1
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| 0, 1, 9446031, 1270004401, 14214075921, 1809702709101, 4614899724711, 6766532724546, 52657436563056, 98855178542676
(list; graph; listen)
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OFFSET
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0,3
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EXAMPLE
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9446031 is triangular and 1306449 is a square.
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MATHEMATICA
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dtn[L_] := Fold[10#1+#2&, 0, L] A={}; For[i=1, i>0, i++, t=i(i-1)/2; r=dtn[Reverse[IntegerDigits[t]]]; If[IntegerQ[Sqrt[r]]&&Mod[t, 10]>0, AppendTo[A, t]; Print[A]]]
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CROSSREFS
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Sequence in context: A015350 A105175 A069376 this_sequence A124515 A075009 A103936
Adjacent sequences: A066700 A066701 A066702 this_sequence A066704 A066705 A066706
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KEYWORD
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base,nonn
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AUTHOR
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Erich Friedman (efriedma(AT)stetson.edu), Jan 14 2002
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EXTENSIONS
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More terms from Jason Earls (zevi_35711(AT)yahoo.com) and the author, Jan 15 2002
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