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PROJECT EULER · #0715

Sextuplet Norms

Statement only · UnsolvedOriginal problem ↗

Let f(n) be the number of 6-tuples (x1,x2,x3,x4,x5,x6) such that:

  • All xi are integers with 0xi<n
  • gcd(x12+x22+x32+x42+x52+x62, n2)=1

Let G(n)=k=1nf(k)k2φ(k)
where φ(n) is Euler's totient function.

For example, G(10)=3053 and G(105)157612967(mod1000000007).

Find G(1012)mod1000000007.

Write-up coming later

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