A069698 Triangular numbers with internal digits 6.

0, 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 66, 78, 91, 465, 561, 666, 861, 46665, 5666661

Offset

1,3

Comments

For proof of finiteness see A069693.

Links

Table of n, a(n) for n=1..20.

Mathematica

Do[ If[ Union[ Drop[ RotateLeft[ IntegerDigits[n(n + 1)/2]], -2]] == {6}, Print[n(n + 1)/2]], {n, 14, 2 10^6}]

Crossrefs

Cf. A069675 to A069684, A069693 to A069700.

Sequence in context: A213516 A078254 A069700 * A069696 A025724 A025746

Adjacent sequences: A069695 A069696 A069697 * A069699 A069700 A069701

Keyword

fini,full,nonn,base

Author

Amarnath Murthy, Apr 06 2002

Extensions

Extended by Robert G. Wilson v, Apr 07 2002

Corrected by Mark Hudson (mrmarkhudson(AT)hotmail.com), Aug 25 2004

Status

approved