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A119073
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Triangular numbers composed of digits {0,4,6}.
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2
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6, 66, 406, 666, 66066, 446040, 600060, 46046406, 440466040, 4040600460, 6604444400406, 4440066066400004040, 644006046066000066046, 44464646466606404046664666, 464440406444064040044646006604604066, 660466006640066446666000606004066646, 60404640400640406040004460664400044060
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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, 4, 6}, 10], IntegerQ[(Sqrt[8 # + 1] - 1)/2] &]] (* Vincenzo Librandi, Dec 18 2015 *)
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PROG
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(Magma) [t: n in [1..2*10^7] | Set(Intseq(t)) subset {0, 4, 6} where t is n*(n+1) div 2]; // Vincenzo Librandi, Dec 18 2015
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CROSSREFS
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See A119033 for a table of cross-references.
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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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