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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.

A173306 Triangle read by rows, generated from an array of terms in powers of triangle A173305.

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 2, 2, 1, 3, 3, 1, 4, 5, 2, 5, 7, 3, 6, 10, 5, 1, 8, 14, 7, 1, 10, 19, 11, 2, 12, 26, 15, 3, 15, 35, 22, 5, 18, 46, 30, 7, 22, 60, 42, 11, 27, 78, 56, 15, 32, 10, 76, 22, 1, 38, 128, 100, 30, 1, 46, 162, 133, 42, 2, 54, 204, 173, 56, 3
Offset: 0

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Author

Gary W. Adamson, Feb 15 2010

Keywords

Comments

Row sums = A000041, the partition numbers.

Examples

			Given triangle A173305, we create an array by extracting terms in powers of A173305:
1, 1, 1, 2, 2, 3, .4, .5, .6, .8, 10, 12, 15,...; = column terms of A173305
1, 1, 2, 3, 4, 6, .9, 12, 16, 22, 29, 38, 50,...; = terms of A173305^2
1, 1, 2, 3, 5, 7, 11, 15, 21, 29, 40, 53, 72,...; = terms of A173305^3
1, 1, 2, 3, 5, 7, 11, 15, 22, 30, 42, 56, 77,...; = terms of A173305^4
...
(rows quickly converge to A000041, the partition numbers).
Taking finite difference terms from the top, we obtain the array:
1, 1, 1, 2, 2, 3, .4, .5, .6,..8, 10, 12, 15,...;
......1, 1, 2, 3, .5, .7, 10, 14, 19, 26, 35,...;
............1, 1, .2, .3, .5, .7, 11, 15, 22,...;
...........................1, .1, .2, .3, .5,...;
...
Finally, columns of the above array become rows of A173306:
1;
1;
1, 1;
2, 1;
2, 2, 1;
3, 3, 1;
4, 5, 2;
5, 7, 3;
6, 10, 5, 1;
8, 14, 7, 1;
10, 19, 11, 2;
12, 26, 15, 3;
15, 35, 22, 5;
18, 46, 30, 7;
22, 60, 42, 11;
27, 78, 56, 15;
32, 100, 76, 22, 1;
38, 128, 100, 30, 1;
46, 162, 133, 42, 2;
54, 204, 173, 56, 3;
...
		

Crossrefs

Formula

Given triangle A173305 in which every column >0 = A000009 shifted down twice.
We create an array in which n-th row = columns in (n-1)-th power of triangle
A173305. Finite differences of successive columns of the array become row terms