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PROJECT EULER · #0463

A Weird Recurrence Relation

Statement only · UnsolvedOriginal problem ↗

The function f is defined for all positive integers as follows:

  • f(1)=1
  • f(3)=3
  • f(2n)=f(n)
  • f(4n+1)=2f(2n+1)f(n)
  • f(4n+3)=3f(2n+1)2f(n)

The function S(n) is defined as i=1nf(i).

S(8)=22 and S(100)=3604.

Find S(337). Give the last 9 digits of your answer.

Write-up coming later

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