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.

A144113 Weight array W={w(i,j)} of the natural number array A038722.

Original entry on oeis.org

1, 2, 1, 3, 1, 2, 4, 1, 1, 3, 5, 1, 1, 1, 4, 6, 1, 1, 1, 1, 5, 7, 1, 1, 1, 1, 1, 6, 8, 1, 1, 1, 1, 1, 1, 7, 9, 1, 1, 1, 1, 1, 1, 1, 8, 10, 1, 1, 1, 1, 1, 1, 1, 1, 9, 11, 1, 1, 1, 1, 1, 1, 1, 1, 1, 10, 12, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 11, 13, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 12, 14, 1, 1, 1, 1, 1, 1, 1, 1, 1
Offset: 1

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Author

Clark Kimberling, Sep 11 2008

Keywords

Comments

In general, let w(i,j) be the weight of the unit square labeled by its northeast vertex (i,j) and for each (m,n), define S(m,n) = Sum_{i=1..m} Sum_{j=1..n} w(i,j).
Then S(m,n) is the weight of the rectangle [0,m]x[0,n]. We call W the weight array of S and we call S the accumulation array of W. For the case at hand, S is the array of natural numbers having the following antidiagonals: (1), then (3,2), then (6,5,4), then (10,9,8,7) and so on.

Examples

			S(2,4)=1+1+2+3+2+1+1+1=14.
		

Crossrefs

Formula

row 1: A000027
row n: n-1 followed by A000012, for n>1.