This page was formerly at:

http://users.eastlink.ca/~sharrywhite/BorderedMagicSquares.html

This site uses the term **Bordered Magic Squares** for
consecutively concentric magic squares. These have the property that
each concentrically inlaid square consists of consecutive integers.

An inlaid square of order **m** can be converted to a **normal
** magic square by subtracting the **(n²+1)/2** of the
border order **n** square and adding **(m²+1)/2**,
which is equivalent to subtracting **(n²-m²)/2**.

The algorithms here were first programmed on the pocket calculators HP-67 and HP-41CV. The bones numbers are computed and, optionally, (n²+1)/2 added to each number to produce the actual square.

The programs are designed to compute one cell number at a time, given the row and
column. A (row, column) is entered to calculate any cell number or, optionally,
the square can be stepped through, computing one cell at a time, by repeatedly
pressing the **R/S** button.

Because the squares are not stored in the calculator, the biggest square that can be made is determined by the number computation and display capacities of the calculator, and, time and patience .

BorderedSquares makes these squares. Squares, up to order 32, can also be made below.

Order5Special makes all the order 5 bordered squares. They can also be made on page border 5.

The order 3 square can be any aspect of the Lo Shu.

To see the **normal** magic square of the order 3 square at the
center of the order 7 square, subtract (7² - 3²)/2 = 20 from the nested
order 3 square numbers. Similarly, subtract (7² - 5²)/2 = 12 for the
nested order 5 square. Similarly, subtract (5² - 3²)/2 = 8 for the
nested order 3 square of the order 5 square.

Imagine an X-axis through the center row and a Y-axis through the center column of each bones. A couple of observations:

- bones are nested: order 7 encloses order 5, which encloses order 3, (which encloses order 1)
- the symmetry is apparent:
- main diagonal numbers are reflected in the center
- between main diagonals, row numbers are reflected in the X-axis
- between main diagonals, column numbers are reflected in the Y-axis
- the sign of the number changes with each reflection

The center 4x4 square can be any aspect of the 880 order 4 squares.

To see the **normal** magic square of the order 4 square at the
center of the order 8 square, subtract (8² - 4²)/2 = 24 from the nested
order 4 square numbers. Similarly, subtract (8² - 6²)/2 = 14 for the
nested order 6 square. Similarly, subtract (6² - 4²)/2 = 10 for the
nested order 4 square of the order 6 square.

Note that ½ has been omitted from all the bones numbers displayed here.

Therefore, to convert these displayed bones numbers to the actual square numbers:

- add n²/2 + 1 to the positive numbers
- add n²/2 to the negative numbers

Again, imagine a horizontal X-axis and a vertical Y-axis through the center of each bones. Some observations:

- bones are nested: order 8 encloses order 6, which encloses order 4
- the symmetry is apparent:
- main diagonal numbers are reflected in the center
- for the order 4, the other numbers are also reflected in the center
- except for order 4:
- between main diagonals, row numbers are reflected in the X-axis
- between main diagonals, column numbers are reflected in the Y-axis

- the sign of the number changes with each reflection

Click **START**.

To make a square:

- enter the
**order** - click
**OK**

To make a bones:

- enter the
**order** - click the
**Make Bones**box - click
**OK**

Note: In the bones displayed here, the minus sign is dropped from
negative numbers. Positive and negative numbers are distinguished by different
colors, (red, blue). Also, ½ is dropped from all numbers for even order
bones.

The software on this site may be used freely.

You should use only if you agree to the
freeware disclaimer.

Please send errata or comments to Harry White, sharrywhite@budshaw.ca

Heinz, Harvey "Glossary" http://www.magic-squares.net/glossary.htm

Nakamura, Mitsutoshi "Terms" http://magcube.la.coocan.jp/magcube/en/terms.htm

Weisstein, Eric W. "Border Square" http://mathworld.wolfram.com/BorderSquare.html

See also: Magic Squares - REFERENCES

Furlow, Warren "The HP-41 Archive Website" http://www.hp41.org/Intro.cfm

Hicks, David G. "The Museum of HP Calculators" http://www.hpmuseum.org/