|
| |
|
|
A145841
|
|
Number of 5-compositions of n
|
|
0
| |
|
|
1, 5, 40, 310, 2395, 18501, 142920, 1104060, 8528890, 65885880, 508970002, 3931805460, 30373291380, 234634403620, 1812556389540, 14002041536004, 108166106338760, 835585763004880, 6454920038905520, 49864411953151840
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
COMMENTS
| A 5-composition of n is a matrix with five rows, such that each column has at least one non zero element and whose elements sum up to n
|
|
|
REFERENCES
| G. Louchard, Matrix compositions: a probabilistic approach, Proceedings of GASCom and Bijective Combinatorics 2008, Bibbiena, Italy, p. 159-170.
E. Munarini, M. Poneti and S. Rinaldi, Matrix compositions, Proceedings of Formal Power Series and Algebraic Combinatorics 2006, San Diego, USA, J. Remmel, M. Zabrocki (Editors) 445-456.
|
|
|
FORMULA
| a(n+5)=10*a(n+4)-20*a(n+3)+20*a(n+2)-10*a(n+1)+2*a(n); G.f.:(1-x)^5/(2(1-x)^5-1)
|
|
|
CROSSREFS
| Cf. A003480 (2-compositions)
Sequence in context: A125729 A144069 A073505 * A123943 A067412 A078846
Adjacent sequences: A145838 A145839 A145840 * A145842 A145843 A145844
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Simone Rinaldi (rinaldi(AT)unisi.it), Oct 21 2008
|
| |
|
|
