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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A228716 Triangle read by rows in which row n lists the rows (including 0's) of the n-th section of the set of partitions (in colexicographic order) of any integer >= n.

Original entry on oeis.org

1, 0, 1, 2, 0, 0, 1, 0, 1, 3, 0, 0, 0, 1, 0, 0, 1, 0, 1, 2, 2, 4, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 3, 2, 5, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 2, 2, 2, 4, 2, 3, 3, 6, 0, 0, 0, 0, 0, 0, 1, 0, 0
Offset: 1

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Author

Omar E. Pol, Sep 02 2013

Keywords

Comments

In other words, row n lists the rows of the last section of the set of partitions (in colexicographic order) of n.
Row lengths is A006128.
The number of zeros in row n is A006128(n-1).
Rows sums give A138879.
For more properties of the sections of the set of partitions of a positive integer see example.
Positive terms give A230440. - Omar E. Pol, Oct 25 2013

Examples

			Illustration of the 15 rows of the 7th section (including zeros) of the set of partitions of any integer >= 7 (hence this is also the last section of the set of partitions of 7). Note that the sum of the k-th column is equal to the number of parts >= k, therefore the first differences of the column sums give the number of occurrences of parts k in the section. The same for all sections of all positive integers, see below:
-----------------------------
Column: 1  2  3  4  5  6  7
-----------------------------
Row |
1   |   0, 0, 0, 0, 0, 0, 1;
2   |   0, 0, 0, 0, 0, 1;
3   |   0, 0, 0, 0, 1;
4   |   0, 0, 0, 0, 1;
5   |   0, 0, 0, 1;
6   |   0, 0, 0, 1;
7   |   0, 0, 1;
8   |   0, 0, 0, 1;
9   |   0, 0, 1;
10  |   0, 0, 1;
11  |   0, 1;
12  |   3, 2, 2;
13  |   5, 2;
14  |   4, 3;
15  |   7;
-----------------------------
Sums:  19, 8, 5, 3, 2, 1, 1 -> Row 7 of triangle A207031.
.       | /| /| /| /| /| /|
.       |/ |/ |/ |/ |/ |/ |
F.Dif: 11, 3, 2, 1, 1, 0, 1 -> Row 7 of triangle A182703.
.
Triangle begins:
[1];
[0,1],[2];
[0,0,1],[0,1],[3];
[0,0,0,1],[0,0,1],[0,1],[2,2],[4];
[0,0,0,0,1],[0,0,0,1],[0,0,1],[0,0,1],[0,1],[3,2],[5];
[0,0,0,0,0,1],[0,0,0,0,1],[0,0,0,1],[0,0,0,1],[0,0,1],[0,0,1],[0,1],[2,2,2],[4,2],[3,3],[6];
[0,0,0,0,0,0,1],[0,0,0,0,0,1],[0,0,0,0,1],[0,0,0,0,1],[0,0,0,1],[0,0,0,1],[0,0,1],[0,0,0,1],[0,0,1],[0,0,1],[0,1],[3,2,2],[5,2],[4,3],[7];
		

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