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A119097
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Triangular numbers composed of digits {1,2,3}.
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2
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1, 3, 21, 231, 2211, 3321, 21321, 32131, 222111, 232221, 11132121, 22221111, 22321221, 2222211111, 2223211221, 12221332311, 222222111111, 222232111221, 1121113113121, 1231322213121, 22222221111111, 22222321111221, 2222222211111111, 2222223211111221
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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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Flatten[Table[Select[FromDigits/@Tuples[{1, 2, 3}, n], IntegerQ[(Sqrt[ 8#+1]- 1)/2]&], {n, 14}]] (* Harvey P. Dale, May 16 2014 *)
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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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