|
| |
|
|
A118565
|
|
Numbers which are both lucky and triangular.
|
|
3
| |
|
|
1, 3, 15, 21, 105, 171, 231, 741, 903, 1275, 1485, 1711, 2211, 2415, 3003, 3403, 3655, 4095, 4465, 4851, 5151, 5253, 5671, 7503, 8001, 8515, 10153, 10585, 10731, 11781, 13203, 13695, 13861, 17391, 18145, 18915, 19503, 21115, 22155, 22791, 24531
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
LINKS
| Donovan Johnson, Table of n, a(n) for n = 1..3537
|
|
|
MATHEMATICA
| triQ[n_] := IntegerQ@Sqrt[8n+1]; lst = Range[1, 26564, 2]; i = 2; While[ i <= (len = Length@lst) && (k = lst[[i]]) <= len, lst = Drop[lst, {k, len, k}]; i++ ]; Select[lst, triQ@# &] (* Robert G. Wilson v *)
|
|
|
CROSSREFS
| Cf. A000959, A000217.
Sequence in context: A147017 A171570 A076825 * A117801 A087674 A009057
Adjacent sequences: A118562 A118563 A118564 * A118566 A118567 A118568
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Luc Stevens (lms022(AT)yahoo.com), May 07 2006
|
|
|
EXTENSIONS
| Corrected and extended by Adam Panagos (adam.panagos(AT)gmail.com) and Robert G. Wilson v (rgwv(at)rgwv.com), May 10 2006
|
| |
|
|
