A119066 Numbers k such that the k-th triangular number contains only digits {0,3,7}.

2, 24, 37, 77, 775, 3943940, 7844837, 124153399, 393193023940, 78406253666877, 256907649052235, 1240997802874797

Offset: 1

Author

Giovanni Resta, May 10 2006

Keywords

• nonn
• base
• more

Comments

Next term exceeds 1.4*10^16.

Links

• G. Resta, Tridigital Triangular Numbers

Crossrefs

Cf. A000217, A119065. See A119034 for a table of cross-references.