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A119079
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Triangular numbers composed of digits {0,5,6}.
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2
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6, 55, 66, 666, 5050, 5565, 6555, 66066, 500500, 600060, 605550, 5656566, 50005000, 60505500, 5000050000, 6050055000, 500000500000, 605000550000, 50000005000000, 60500005500000, 66605656050060, 550006056055665, 555665666566566, 5000000050000000
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OFFSET
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1,1
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LINKS
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FORMULA
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MATHEMATICA
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Rest[Select[FromDigits/@Tuples[{0, 5, 6}, 15], IntegerQ[(Sqrt[8#+1]-1)/2]&]] (* Harvey P. Dale, Nov 19 2013 *)
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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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