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A119098 Numbers n such that the n-th triangular number contains only digits {1,2,3}. 2

%I

%S 1,2,6,21,66,81,206,253,666,681,4718,6666,6681,66666,66681,156341,

%T 666666,666681,1497406,1569281,6666666,6666681,66666666,66666681,

%U 666666666,666666681,6528600666,6666666666,6666666681,66666666666

%N Numbers n such that the n-th triangular number contains only digits {1,2,3}.

%H G. Resta, <a href="http://www.numbersaplenty.com/tr/tr123.html">Tridigital Triangular Numbers</a>

%Y Cf. A000217, A119097. See A119034 for a table of cross-references.

%K nonn,base

%O 1,2

%A _Giovanni Resta_, May 10 2006

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Last modified October 1 08:39 EDT 2020. Contains 337442 sequences. (Running on oeis4.)