cp's OEIS Frontend

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.

A153206 Convolution triangle by rows, T(n,k) = A153197(n-k) * A153198.

Original entry on oeis.org

1, 1, 1, 2, 1, 2, 5, 2, 2, 5, 15, 5, 4, 5, 14, 51, 15, 10, 10, 14, 43, 189, 51, 30, 25, 28, 43, 143, 748, 189, 102, 75, 70, 86, 143, 509, 3128, 748, 378, 255, 210, 215, 286, 509, 1922, 13731, 3128, 1496, 945, 714, 645, 715, 1018, 1922, 7651
Offset: 0

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Author

Gary W. Adamson, Dec 20 2008

Keywords

Comments

A153197 prefaced with a 1: (1, 1, 2, 5, 15, 51,...) convolved with A006789 (1, 1, 2, 5, 14, 43,...) = A006789 shifted: (1, 2, 5, 14, 43, 143,...).
Right border = A006789, row sums = A006789 shifted.

Examples

			First few rows of the triangle =
1;
1, 1;
2, 1, 2;
5, 2, 2, 5;
15, 5, 4, 5, 14;
51, 15, 10, 10, 14, 43;
189, 51, 30, 25, 28, 43, 143;
748, 189, 102, 75, 70, 86, 143, 509;
3128, 748, 378, 255, 210, 215, 286, 509, 1922;
13731, 3128, 1496, 945, 714, 645, 715, 1018, 1922, 7651;
62969, 13731, 6256, 3740, 2646, 2193, 2145, 2545, 3844, 7651, 31965;
...
Row 5 = (51, 15, 10, 10, 14, 43), = termwise products of (51, 15, 5, 2, 1, 1) and (1, 1, 2, 5, 14, 43), where A153197 = (1, 2, 5, 15, 51,...); and A006789 = (1, 1, 2, 5, 14, 43,...).
		

Crossrefs

Formula

Convolution triangle by rows, T(n,k) = A153197(n-k) * A153198 = a * b, where a = an infinite lower triangular matrix with A153197 prefaced with a 1: (1, 1, 2, 5, 15, 51, 189, 748,...) in every column; and b = an infinite lower triangular matrix with A006789 in the main diagonal and the rest zeros.