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A119113
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Triangular numbers composed of digits {1,3,5}.
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2
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1, 3, 15, 55, 153, 351, 5151, 33153, 35511, 3531153, 3555111, 35133153, 51151555, 51313515, 355311153, 355551111, 1553111511, 5135151153, 5351313331, 15533353153, 35553111153, 35555511111, 153335313531, 155315331153, 315331155153, 355333351555, 1353153151155
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OFFSET
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1,2
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LINKS
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FORMULA
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MATHEMATICA
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Select[Accumulate[Range[1000000]], Union[Drop[DigitCount[#], {1, 5, 2}]]=={0}&] (* Harvey P. Dale, Apr 16 2011 *)
Table[Select[FromDigits/@Tuples[{1, 3, 5}, n], OddQ[Sqrt[8#+1]]&], {n, 12}]//Flatten (* Harvey P. Dale, Aug 02 2022 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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