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.

A157927 Joint-rank array of the numbers i^2+j^2, where i>=0, j>=0.

Original entry on oeis.org

1, 2, 2, 4, 3, 4, 7, 5, 5, 7, 10, 8, 6, 8, 10, 14, 11, 9, 9, 11, 14, 19, 15, 13, 12, 13, 15, 19, 24, 20, 16, 14, 14, 16, 20, 24, 30, 25, 21, 18, 17, 18, 21, 25, 30, 37, 31, 27, 23, 22, 22, 23, 27, 31, 37, 44, 38, 32, 28, 26, 25, 26, 28, 32, 38, 44
Offset: 1

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Author

Clark Kimberling, Dec 17 2010

Keywords

Comments

The definition of joint-rank array given at A182801 is
here extended to arrays R={f(i,j)} for which the numbers
f(i,j) are not necessarily distinct. Specifically, all
duplicates are assigned the same rank when all the numbers
in R are jointly ranked. Let {a(i,j)} denote the
resulting joint-rank array. In case all f(i,j) are
positive integers, a(i,j)=f(i,j)-L(i,j), where L(i,j) is
the number of numbers in R that are <=f(i,j).
(Row 1)=A047808.

Examples

			A corner of the array R={i^2+j^2} is
0....1....4....9...16...
1....2....5...10...17...
4....5....8...13...20...
9...10...13...18...25...
Replace each term of R by its rank:
1....2....4....7...10...
2....3....5....8...11...
4....5....6....9...13...
7....8....9...12...14...
		

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