TABLE OF RIGHT DIAGONALS

GENERATION OF RIGHT DIAGONALS FOR MAGIC SQUARE OF SQUARES (Part IIB)

Picture of a square

Square of Squares Tables

Andrew Bremner's article on squares of squares included the 3x3 square:

Bremner's square
373228925652
3607214252232
20525272222121

The numbers in the right diagonal as the tuple (205,2425,25652) appear to have been obtained from elsewhere. But I will show that this sequence is part of a larger set of tuples having the same property, i.e. the first number in the tuple when added to a difference (Δ) gives the second square in the tuple and when this same (Δ) is added to the second square produces a third square. All these tuple sequences can be used as entries into the right diagonal of a magic square.

It was shown previously that these numbers are a part of a sequence of squares and this page is a continuation of that effort.

I will show from scratch, (i.e. from first principles) that these tuples (a2,b2,c2) whose sum a2 + b2 + c23b2 = 0 are generated from another set of tuples that (except for the initial set of tuples) obeys the equation a2 + b2 + c23b20.

Find the Initial Tuples

As was shown in the web page Generation of Right Diagonals, the first seven tuples of real squares, are generated using the formula c2 = 2b2 − 1 and placed into table T below. The first number in each tuple all a start with +1 which employ integer numbers as the initial entry in the diagonal.

The desired c2 is calculated by searching all b numbers between 1 and 100,000. However, it was found that the ratio of bn+1/bn or cn+1/cn converges on (1 + √2)2 as the b's or c's get larger. This means that moving down each row on the table each integer value takes on the previous bn or cn multiplied by (1 + √2)2, i.e., 5.8284271247...

Furthermore, this table contains seven initial tuples in which all a start with −1 instead as of +1 as was shown in Part IIA. The initial simple tuple (−1,1,1) is the only tuple stands on its own. Our first example is then (−1, 29, 41).

Table T
anbncn
−111
−157
−12941
−1169239
−19851393
−157418119
−13346147321

Construction of two Tables of Right Diagonal Tuples

  1. The object of this exercise is to generate a table with a set of tuples that obey the rule: a2 + b2 + c23b20
    and convert these tuples into a second set of tuples that obey the rule: a2 + b2 + c23b2 = 0.
  2. To generate table I we take the tuple (−1,29,41) and add 2 to each entry in the tuple to produce Table I with +1 entries in the first column.
  3. We also set a condition for table I. We need to know two numbers e and g where g = 2e and which when added to the second and third numbers, respectively, in the tuple of table I produce the two numbers in the next row of table I.
  4. Table I
    13143
    131+e43+g
  5. These numbers, e and g are not initially known but a mathematical method will be shown below on how to obtain them. Having these numbers on hand we can then substitute them into the tuple equation 12 + (en + 29)2 + (gn + 41)2 − 3(en +29)2 along with n (the order), the terms squared and summed to obtain a value S which when divided by a divisor d produces a number f.
  6. This number f when added to the square of each member in the tuple (1,b,c) generates (f + 1)2 + (f + en + 29)2 + f + gn + 41)2 − 3(f + en +29)2 producing the resulting tuple in table II. This is the desired tuple obeying the rule a2 + b2 + c23b2 = 0.
  7. Table I
    13143
    131+e43+g
    Table II
    13143
    1 + f31+e + f 43+g + f
  8. The Δs are calculated, the difference in Table 2 between columns 2 or 3, and the results placed in the last column.
  9. Note that the third column in Table II is identical to column 2 but shifted up three rows.
  10. The final tables produced after the algebra is performed are shown below:
n
0
1
2
3
4
5
6
7
8
9
10
11
12
Table I
13143
13755
14367
14979
15591
161103
167115
173127
179139
185151
191163
197175
1103187
f = S/d
−2
8
22
40
62
88
118
152
190
232
278
328
382
Table II
−12943
94563
236589
4189119
63117153
89149191
119185233
153225279
191269329
233317383
279369441
329425503
383485569
Δ
840
1944
3696
6240
9720
14280
20064
27216
35880
46200
58320
72384
88536

To obtain e, g,  f  and d the algebraic calculations are performed as follows:

Thus the values of the rows in both tables can be obtain by using a little arithmetic as was shown above or we can employ the two mathematical equations to generate each row. The advantage of using this latter method is that any n can be used. With the former method one calculation after another must be performed until the requisite n is desired.


  1. Square A example of a magic square of order number n = 0 produced from the tuple (-1, 29, 41). Squares B and C are magic squares of order n = 14 produced from the tuple (503, 617, 713). The magic sums in this case are 2523 and 1142067, respectively.
Magic square A
372-527412
1153292232
(-1)2472313
  
Magic square B
38624847027132
74006261721462
50325262612382
  
Magic square C
8022-95067132
24585461727182
50328782118174

This concludes Part IIB. To continue to Part III.
Go back to homepage.


Copyright © 2011 by Eddie N Gutierrez. E-Mail: edguti144@outlook.com