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Search: id:A066742
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| A066742 |
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Square numbers whose reverse is pentagonal. |
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+0
1
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| 0, 1, 529, 1089, 2116, 6241, 103041, 26222944225, 2648772525025, 6262611355441, 62443279235236
(list; graph; listen)
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OFFSET
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0,3
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EXAMPLE
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925 is pentagonal, and 529 is square
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MATHEMATICA
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dtn[L_] := Fold[10#1+#2&, 0, L] A={0}; For[i=1, i>0, i++, t=i(3i-1)/2; r=dtn[Reverse[IntegerDigits[t]]]; If[IntegerQ[Sqrt[r]]&&Mod[t, 10]>0, AppendTo[A, r]; Print[A]]]
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CROSSREFS
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Adjacent sequences: A066739 A066740 A066741 this_sequence A066743 A066744 A066745
Sequence in context: A045788 A020289 A082409 this_sequence A067475 A052074 A112079
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KEYWORD
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base,more,nonn
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AUTHOR
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Erich Friedman (efriedma(AT)stetson.edu), Jan 16 2002
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