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%I #8 Jul 13 2021 01:24:14
%S 3,11,36,115,363,1095,11576,36624,363504,391576,391588,36333648,
%T 123288823,3660785999,11014541352775,39410677756315,124633627940188
%N Numbers k such that the k-th triangular number contains only digits {0,6,7}.
%C Next term exceeds 1.4*10^16.
%H G. Resta, <a href="http://www.numbersaplenty.com/tr/tr067.html">Tridigital Triangular Numbers</a>
%Y Cf. A000217, A119087. See A119034 for a table of cross-references.
%K nonn,base,more
%O 1,1
%A _Giovanni Resta_, May 10 2006