A117834 Triangular numbers with consecutive digits.

0, 1, 3, 6, 10, 21, 45, 78, 210

Offset

1,3

Comments

Digits can be in ascending or descending order. After 9 comes 0.

Next term, if there is one, has more than 300 digits. - Joshua Zucker, May 11 2006

Terms correspond to (some) integral points on a finite number of Mordell curves. Thus there is only a finite number of terms. It is likely that no other terms besides those listed exist. - Max Alekseyev, Oct 08 2023

Links

Table of n, a(n) for n=1..9.

Crossrefs

Cf. A000217.

Sequence in context: A068149 A068709 A068804 * A317857 A346733 A220827

Adjacent sequences: A117831 A117832 A117833 * A117835 A117836 A117837

Keyword

base,fini,more,nonn

Author

Luc Stevens (lms022(AT)yahoo.com), Apr 30 2006

Status

approved