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PROJECT EULER · #0542

Geometric Progression with Maximum Sum

Statement only · UnsolvedOriginal problem ↗

Let S(k) be the sum of three or more distinct positive integers having the following properties:

  • No value exceeds k.
  • The values form a geometric progression.
  • The sum is maximal.

S(4)=4+2+1=7
S(10)=9+6+4=19
S(12)=12+6+3=21
S(1000)=1000+900+810+729=3439

Let T(n)=k=4n(1)kS(k).
T(1000)=2268

Find T(1017).

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