Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A105806
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A105806 Triangle of number of partitions of n with nonnegative Dyson rank r=0,1,...,n-1. +0
4
1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 2, 1, 1, 0, 1, 3, 1, 2, 1, 1, 0, 1, 2, 3, 2, 2, 1, 1, 0, 1, 4, 3, 3, 2, 2, 1, 1, 0, 1, 4, 5, 3, 4, 2, 2, 1, 1, 0, 1, 6, 5, 6, 3, 4, 2, 2, 1, 1, 0, 1, 7, 8, 6, 6, 4, 4, 2, 2, 1, 1, 0, 1, 11, 8, 9, 7, 6, 4, 4, 2, 2, 1, 1, 0, 1, 11, 13, 10, 10, 7, 7, 4, 4, 2, 2, 1, 1 (list; table; graph; listen)
OFFSET

1,17

COMMENT

The array with all ranks (including negative ones) is A063995.

a(n,-r)=a(n,r) for negative rank -r with r from 1,2,...,n-1 (due to conjugation of partitions of n; see the link).

Dyson's rank of a partition of n is the maximal part minus the number of parts, i.e. the number of columns minus the number of rows of the Ferrers diagram (see the link) of the partition.

REFERENCES

F. J. Dyson: Problems for solution nr. 4261, Am. Math. Month. 54 (1947) 418.

LINKS

Eric Weisstein's World of Mathematics, Conjugation of partitions of n.

Eric Weisstein's World of Mathematics, Ferrers diagram.

W. Lang: First 16 rows.

FORMULA

a(n, r)= number of partitions of n with rank r, with r from 0, 1, ..., n-1.

EXAMPLE

Rows [1]; [0,1]; [1,0,1]; [1,1,0,1]; [1,1,1,0,1]; [1,2,1,1,0,1]...

Row 6, second entry is 2 because there are 2 partitions of n=6 with rank r=2-1=1, namely (3^2) and (1^2,4).

CROSSREFS

Columns for r=0..3 are given in: A047993, A101198, A101199, A101200, ...

Row sums = A064174.

Sequence in context: A059571 A027052 A131257 this_sequence A129501 A092921 A029387

Adjacent sequences: A105803 A105804 A105805 this_sequence A105807 A105808 A105809

KEYWORD

nonn,easy,tabl

AUTHOR

Wolfdieter Lang (wolfdieter.lang_AT_physik_DOT_uni-karlsruhe_DOT_de), Mar 11 2005

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified July 25 07:41 EDT 2008. Contains 142293 sequences.


AT&T Labs Research