|
Search: id:A085782
|
|
|
| A085782 |
|
Numbers that can be written as a product of triangular numbers. |
|
+0
3
|
|
| 0, 1, 3, 6, 9, 10, 15, 18, 21, 27, 28, 30, 36, 45, 54, 55, 60, 63, 66, 78, 81, 84, 90, 91, 100, 105, 108, 120, 126, 135, 136, 150, 153, 162, 165, 168, 171, 180, 189, 190, 198, 210, 216, 225, 231, 234, 243, 252, 253, 270, 273, 276, 280, 300, 315, 324, 325, 330, 351
(list; graph; listen)
|
|
|
OFFSET
|
1,3
|
|
|
COMMENT
|
These are the numbers that appear at least once in A007425 (the number of ordered factorizations of n as n = rst). - Matthew Vandermast (ghodges14(AT)comcast.net), Jul 26 2003
Contains A085780 as a subsequence (exactly 2 factors); 27,54,81,... are the first elements in the complement. - M. F. Hasler (www.univ-ag.fr/~mhasler), Apr 03 2008
|
|
EXAMPLE
|
54=6*3*3=t(3)*t(2)*t(2)
|
|
CROSSREFS
|
Cf. A000217.
Sequence in context: A113502 A061904 A111359 this_sequence A085780 A166047 A107084
Adjacent sequences: A085779 A085780 A085781 this_sequence A085783 A085784 A085785
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Jon Perry (perry(AT)globalnet.co.uk), Jul 23 2003
|
|
EXTENSIONS
|
More terms from Max Alekseyev (maxale(AT)gmail.com) and Jon E. Schoenfield (jonscho(AT)hiwaay.net), Sep 04 2009
|
|
|
Search completed in 0.002 seconds
|
