Determining if this degree sequence is graphic

in the rye
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Homework Statement


Determine if the degree sequence 3,3,2,2,2,2 is graphic.

Homework Equations


Havel-Hakimi

The Attempt at a Solution


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Check to see if the sum is even:
3+3+2+2+2+2 = 16It is even, therefore apply Havel-Hakimi

3,3,2,2,2,2 -> remove the 3 and subtract the next 3 by 1
2,1,1,2,2 -> remove the 2 and subtract the next 2 by 1
0,0,2,2 -> reorder from largest to smallest
2,2,0,0 -> remove the 2 and subtract 1 from the next 2
1,-1,0 -> reached a negative, stop

Therefore the sequence is not graphic.

The solution says it is graphic and provides no explanation.

Am I misunderstanding Havel-Hakimi Theorem?
 
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Maybe I don't understand your steps. It looks to me like you did not reorder every time it was necessary to make the sequence non-increasing.
 
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FactChecker said:
Maybe I don't understand your steps. It looks to me like you did not reorder every time it was necessary to make the sequence non-increasing.
Facepalm. I completely missed that... I went back an re-looked at the problem before coming back to this post. It worked out when I applied the alogorithm correctly... thanks haha
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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