A119141 Numbers k such that the k-th triangular number contains only digits {1,6,7}.

1, 3, 11, 18, 36, 48, 58, 188, 351, 366, 576, 1111, 3941, 11106, 12423, 17981, 18263, 34976, 365423, 392711, 585963, 1111411, 1494106, 568817576, 1494099506, 3651623506, 12382820048, 351330663666, 586117934576, 37888432565023

Offset: 1

Author

Giovanni Resta, May 10 2006

Keywords

• nonn
• base

Links

• G. Resta, Tridigital Triangular Numbers

Crossrefs

Cf. A000217, A119140. See A119034 for a table of cross-references.