login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A136102 Triangle read by rows, in which rows give signatures for Ferrers boards fitting inside staircases coded 1, 2, 12, 360, 75600, ... (see A006939). 2
1, 1, 2, 1, 2, 4, 6, 12, 1, 2, 4, 6, 8, 12, 24, 30, 36, 60, 72, 120, 180, 360, 1, 2, 4, 6, 8, 12, 16, 24, 30, 36, 48, 60, 72, 120, 144, 180, 210, 216, 240, 360, 420, 32, 720, 840, 900, 1080, 1260, 1680, 1800, 2160, 2520, 3600, 5040, 5400, 6300, 7560, 10800, 12600 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
The number of signatures on each row is 1 2 5 14 42 132 ... cf. A000108.
REFERENCES
G. E. Andrews and K. Eriksson, Integer Partitions, Cambridge Univ. Press, 2004. page 22 Exer. 33.
LINKS
EXAMPLE
The irregular array begins
1
1 2
1 2 4 6 12
1 2 4 6 8 12 24 30 36 60 72 120 180 360
CROSSREFS
Sequence in context: A112179 A058553 A038067 * A366883 A306810 A325747
KEYWORD
easy,nonn,tabf
AUTHOR
Alford Arnold, Jan 12 2008
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 28 17:42 EDT 2024. Contains 371254 sequences. (Running on oeis4.)