Arrange the numbers 1 through 10 in the shape of a pyramid

In summary, the conversation discusses arranging numbers in the shape of a pyramid, with each number being equal to the difference of the two numbers directly below it. There are eight solutions for one level, six solutions for two levels, and potentially eight solutions for three levels. The conversation also touches on the placement of certain numbers (such as 10, 8, 9, 6, 5, 4, and 7) in relation to the bottom of the pyramid.
  • #1
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Arrange the numbers 1 through 10 in the shape of a pyramid (1 number at the peak, 2 numbers in the next row down, 3 in the next row, and 4 in the bottom row). The numbers must be arranged such that each number is equal to the difference of the two numbers directly below it. For example, if 5 and 1 are next to each other in the same row, then 4 must be placed on top of them.
 
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  • #2
3
7 4
2 9 5
8 10 1 6
It represents a pyramid, though I'm unable to give to it a pyramidal shape
 
  • #3
It looks good, but if you're reall picky you can use the code tag for fixed spacing

Code:
   3
  7 4
 2 9 5
8 A 1 6

I wonder if the solution is unique. Apparently not:

Code:
   3
  2 5
 7 9 4
8 1 A 6
 
Last edited:
  • #4
There are eight solutions:

{3, 2, 5, 7, 9, 4, 8, 1, 10, 6},
{3, 4, 7, 5, 9, 2, 6, 1, 10, 8},
{3, 5, 2, 4, 9, 7, 6, 10, 1, 8},
{3, 7, 4, 2, 9, 5, 8, 10, 1, 6},
{4, 1, 5, 6, 7, 2, 9, 3, 10, 8},
{4, 2, 6, 5, 7, 1, 8, 3, 10, 9},
{4, 5, 1, 2, 7, 6, 8, 10, 3, 9},
{4, 6, 2, 1, 7, 5, 9, 10, 3, 8}

- Warren
 
  • #5
For 1 level, there are 4 solutions:

2 / 1 3
2 / 3 1
1 / 2 3
1 / 3 2

3 always appears on the bottom.

For 2 levels, there are 6 solutions:

2 / 3 5 / 4 1 6
2 / 5 3 / 6 1 4
1 / 3 4 / 5 2 6
1 / 4 3 / 6 2 5
3 / 4 1 / 2 6 5
3 / 1 4 / 5 6 2

6 always appears on the bottom. 5 and 4 appear on the bottom two levels, with only one of these at the highest.

I trust there are no more than 8 solutions for 3 levels:

3 / 4 7 / 5 9 2 / 6 1 A 8
3 / 7 4 / 2 9 5 / 8 A 1 6
3 / 2 5 / 7 9 4 / 8 1 A 6
3 / 5 2 / 4 9 7 / 6 A 1 8
4 / 2 6 / 5 7 1 / 8 3 A 9
4 / 6 2 / 1 7 5 / 9 A 3 8
4 / 1 5 / 6 7 2 / 9 3 A 8
4 / 5 1 / 2 7 6 / 8 A 3 9

10 always appears on the bottom. 8 and 9 appear on the bottom two levels. (In fact 8 is always on the bottom.) 5, 6, and 7 appear on the bottom three levels, with only one of these at the highest.

What a great way to waste time...
 
  • #6
meteor with the point, good work chroot and davilla!
 

1. How do you arrange the numbers 1 through 10 in the shape of a pyramid?

To arrange the numbers 1 through 10 in the shape of a pyramid, you would start by placing 1 at the top, followed by 2 and 3 on the second row, 4, 5, and 6 on the third row, and finally 7, 8, 9, and 10 on the bottom row.

2. What is the total number of rows in the pyramid?

The total number of rows in the pyramid is 4.

3. How many numbers are used in the pyramid?

There are 10 numbers used in the pyramid, from 1 to 10.

4. Can the numbers be arranged in a different shape?

Yes, the numbers can be arranged in different shapes, such as a square or a triangle, but the pyramid shape is the most common and visually appealing.

5. What is the sum of all the numbers in the pyramid?

The sum of all the numbers in the pyramid is 55.

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