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!)
A228350 Triangle read by rows: T(j,k) is the k-th part in nonincreasing order of the j-th region of the set of compositions (ordered partitions) of n in colexicographic order, if 1<=j<=2^(n-1) and 1<=k<=A006519(j). 7
1, 2, 1, 1, 3, 2, 1, 1, 1, 2, 1, 1, 4, 3, 2, 2, 1, 1, 1, 1, 1, 2, 1, 1, 3, 2, 1, 1, 1, 2, 1, 1, 5, 4, 3, 3, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 3, 2, 1, 1, 1, 2, 1, 1, 4, 3, 2, 2, 1, 1, 1, 1, 1, 2, 1, 1, 3, 2, 1, 1, 1, 2, 1, 1, 6, 5, 4, 4, 3, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Triangle read by rows in which row n lists the A006519(n) elements of the row A001511(n) of triangle A065120, n >= 1.
The equivalent sequence for integer partitions is A206437.
LINKS
FORMULA
T(j,k) = A065120(A001511(j)),k) = A001511(j) - A029837(k), 1<=k<=A006519(j), j>=1.
EXAMPLE
---------------------------------------------------------
. Diagram Triangle
Compositions of of compositions (rows)
. of 5 regions and regions (columns)
----------------------------------------------------------
. _ _ _ _ _
. 5 |_ | 5
. 1+4 |_|_ | 1 4
. 2+3 |_ | | 2 3
. 1+1+3 |_|_|_ | 1 1 3
. 3+2 |_ | | 3 2
. 1+2+2 |_|_ | | 1 2 2
. 2+1+2 |_ | | | 2 1 2
. 1+1+1+2 |_|_|_|_ | 1 1 1 2
. 4+1 |_ | | 4 1
. 1+3+1 |_|_ | | 1 3 1
. 2+2+1 |_ | | | 2 2 1
. 1+1+2+1 |_|_|_ | | 1 1 2 1
. 3+1+1 |_ | | | 3 1 1
. 1+2+1+1 |_|_ | | | 1 2 1 1
. 2+1+1+1 |_ | | | | 2 1 1 1
. 1+1+1+1+1 |_|_|_|_|_| 1 1 1 1 1
.
Also the structure could be represented by an isosceles triangle in which the n-th diagonal gives the n-th region. For the composition of 4 see below:
. _ _ _ _
. 4 |_ | 4
. 1+3 |_|_ | 1 3
. 2+2 |_ | | 2 2
. 1+1+2 |_|_|_ | 1 1 2
. 3+1 |_ | | 3 1
. 1+2+1 |_|_ | | 1 2 1
. 2+1+1 |_ | | | 2 1 1
. 1+1+1+1 |_|_|_|_| 1 1 1 1
.
Illustration of the four sections of the set of compositions of 4:
. _ _ _ _
. |_ | 4
. |_|_ | 1+3
. |_ | | 2+2
. _ _ _ |_|_|_ | 1+1+2
. |_ | 3 | | 1
. _ _ |_|_ | 1+2 | | 1
. _ |_ | 2 | | 1 | | 1
. |_| 1 |_| 1 |_| 1 |_| 1
.
.
Illustration of initial terms. The parts of the eight regions of the set of compositions of 4:
--------------------------------------------------------
\j: 1 2 3 4 5 6 7 8
k
--------------------------------------------------------
. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
1 |_|1 |_ |2 |_|1 |_ |3 |_|1 |_ |2 |_|1 |_ |4
2 |_|1 |_ |2 |_|1 |_ |3
3 | |1 | |2
4 |_|1 |_ |2
5 | |1
6 | |1
7 | |1
8 |_|1
.
Triangle begins:
1;
2,1;
1;
3,2,1,1;
1;
2,1;
1;
4,3,2,2,1,1,1,1;
1;
2,1;
1;
3,2,1,1;
1;
2,1;
1;
5,4,3,3,2,2,2,2,1,1,1,1,1,1,1,1;
...
.
Also triangle read by rows T(n,m) in which row n lists the parts of the n-th section of the set of compositions of the integers >= n, ordered by regions. Row lengths give A045623. Row sums give A001792 (see below):
[1];
[2,1];
[1],[3,2,1,1];
[1],[2,1],[1],[4,3,2,2,1,1,1,1];
[1],[2,1],[1],[3,2,1,1],[1],[2,1],[1],[5,4,3,3,2,2,2,2,1,1,1,1,1,1,1,1];
CROSSREFS
Main triangle: column 1 is A001511. Row j has length A006519(j). Row sums give A038712.
Sequence in context: A030312 A030321 A030305 * A220482 A084580 A263633
KEYWORD
nonn,tabf
AUTHOR
Omar E. Pol, Aug 20 2013
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 May 8 19:26 EDT 2024. Contains 372341 sequences. (Running on oeis4.)