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A119054
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Numbers k such that the k-th triangular number contains only digits {0,2,6}.
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2
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3, 11, 36, 363, 1095, 3640, 72396, 2097628, 1119484011, 11489670148, 200329741476, 666663663636, 6666633636651, 11508483829424, 203306006810436
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OFFSET
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1,1
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COMMENTS
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LINKS
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MATHEMATICA
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Select[Range[2 10^7], Complement[IntegerDigits[Binomial[# + 1, 2]], {0, 2, 6}] == {} &] (* Vincenzo Librandi, Dec 25 2015 *)
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PROG
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(Magma) [n: n in [1..4*10^6] | Set(Intseq(Binomial(n+1, 2))) subset [0, 2, 6]]; // Vincenzo Librandi, Dec 25 2015
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CROSSREFS
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KEYWORD
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nonn,base,more
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AUTHOR
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STATUS
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approved
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