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

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The discussion revolves around arranging the numbers 1 through 10 in a pyramid structure where each number at a higher level equals the difference of the two numbers directly below it. Participants share various configurations that meet this criterion, revealing that there are multiple solutions to the problem. Specifically, it is noted that there are eight distinct arrangements for the pyramid, with examples provided to illustrate these configurations. The conversation also touches on the uniqueness of solutions for smaller pyramid levels, confirming that for one level there are four solutions, and for two levels, six solutions can be derived. The participants express appreciation for the challenge, highlighting the engaging nature of the puzzle.
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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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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
 
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:
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
 
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...
 

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