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PROJECT EULER · #0438

Integer Part of Polynomial Equation's Solutions

Statement only · UnsolvedOriginal problem ↗

For an n-tuple of integers t=(a1,,an), let (x1,,xn) be the solutions of the polynomial equation xn+a1xn1+a2xn2++an1x+an=0.

Consider the following two conditions:

  • x1,,xn are all real.
  • If x1,,xn are sorted, xi=i for 1in. (: floor function.)

In the case of n=4, there are 12 n-tuples of integers which satisfy both conditions.
We define S(t) as the sum of the absolute values of the integers in t.
For n=4 we can verify that S(t)=2087 for all n-tuples t which satisfy both conditions.

Find S(t) for n=7.

Write-up coming later

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