A119147 Numbers k such that the k-th triangular number contains only digits {1,7,8}.

1, 12, 18, 58, 132, 153, 1332, 1541, 6018, 11981, 13332, 40278, 124753, 133332, 603121, 1332507, 1333332, 13332507, 13333332, 19072906, 133332507, 133333332, 485569333, 486040907, 612880278, 1247972658, 1333332507

Offset

1,2

Links

Table of n, a(n) for n=1..27.

G. Resta, Tridigital Triangular Numbers

Crossrefs

Cf. A000217, A119146. See A119034 for a table of cross-references.

Sequence in context: A259263 A341039 A279369 * A370395 A226176 A177426

Adjacent sequences: A119144 A119145 A119146 * A119148 A119149 A119150

Keyword

nonn,base

Author

Giovanni Resta, May 10 2006

Status

approved