[seqfan] Cannot reproduce A328980

[Lars Blomberg]

Hello Seqfans, 

 

A328980 - Number of solutions to Erdos's Last Equation in n variables.


 

Unfortunately, I have no access to the referenced paper, but I infer that
only non-negative x_i are permitted and that solutions with the same
product/sum value are only counted once.

Then I can reproduce n=2,3,4,5 but for n=6,7 the values differ as shown
below.

 

Regards,

Lars

 

a(2) = 2

1: (0, 0)  0  0

2: (3, 6)  18  18

3: (4, 4)  16  16

 

a(3) = 7

1: (0, 0, 0)  0  0

2: (1, 4, 15)  60  60

3: (1, 5, 9)  45  45

4: (1, 6, 7)  42  42

5: (2, 2, 12)  48  48

6: (2, 3, 5)  30  30

7: (3, 3, 3)  27  27

 

a(4) = 8

1: (0, 0, 0, 0)  0  0

2: (1, 1, 5, 28)  140  140

3: (1, 1, 6, 16)  96  96

4: (1, 1, 7, 12)  84  84

5: (1, 1, 8, 10)  80  80

6: (1, 2, 3, 12)  72  72

7: (1, 2, 4, 7)  56  56

8: (1, 3, 4, 4)  48  48

 

a(5) = 8

1: (0, 0, 0, 0, 0)  0  0

2: (1, 1, 1, 6, 45)  270  270

3: (1, 1, 1, 7, 25)  175  175

4: (1, 1, 1, 9, 15)  135  135

5: (1, 1, 1, 10, 13)  130  130

6: (1, 1, 2, 3, 35)  210  210

7: (1, 1, 2, 5, 9)  90  90

8: (1, 1, 3, 5, 5)  75  75

 

a(6) = 16, OEIS has 17

1: (0, 0, 0, 0, 0, 0)  0  0

2: (1, 1, 1, 1, 7, 66)  462  462

3: (1, 1, 1, 1, 8, 36)  288  288

4: (1, 1, 1, 1, 9, 26)  234  234

5: (1, 1, 1, 1, 10, 21)  210  210

6: (1, 1, 1, 1, 11, 18)  198  198

7: (1, 1, 1, 1, 12, 16)  192  192

8: (1, 1, 1, 2, 4, 27)  216  216

9: (1, 1, 1, 2, 5, 15)  150  150

10: (1, 1, 1, 2, 6, 11)  132  132

11: (1, 1, 1, 2, 7, 9)  126  126

12: (1, 1, 1, 3, 3, 18)  162  162

13: (1, 1, 1, 3, 4, 10)  120  120

14: (1, 1, 1, 3, 6, 6)  108  108

15: (1, 1, 2, 2, 4, 6)  96  96

16: (1, 1, 2, 3, 3, 5)  90  90

 

a(7) = 15, OEIS has 14

1: (0, 0, 0, 0, 0, 0, 0)  0  0

2: (1, 1, 1, 1, 1, 8, 91)  728  728

3: (1, 1, 1, 1, 1, 9, 49)  441  441

4: (1, 1, 1, 1, 1, 10, 35)  350  350

5: (1, 1, 1, 1, 1, 11, 28)  308  308

6: (1, 1, 1, 1, 1, 13, 21)  273  273

7: (1, 1, 1, 1, 1, 14, 19)  266  266

8: (1, 1, 1, 1, 2, 4, 70)  560  560

9: (1, 1, 1, 1, 2, 7, 13)  182  182

10: (1, 1, 1, 1, 3, 3, 35)  315  315

11: (1, 1, 1, 1, 3, 7, 7)  147  147

12: (1, 1, 1, 1, 4, 5, 7)  140  140

13: (1, 1, 1, 2, 2, 2, 63)  504  504

14: (1, 1, 1, 2, 2, 3, 14)  168  168

15: (1, 1, 1, 2, 3, 3, 7)  126  126