[IMO-1981] Find f(3, 2023) when f(x, y) satisfy certain rules

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  • čas přidán 25. 10. 2023
  • Find f(3, 2023) if f(0,y)=y+1, f(x+1,0)=f(x,1), f(x+1,y+1)=f(x,f(x+1,y)).
    This is a question from IMO-1981 and the approach is now widely used in a type of computer algorithm.

Komentáře • 2

  • @PantheraLeo04
    @PantheraLeo04 Před 8 měsíci +1

    This was a really great video, you did a great job breaking down the problem. But I have one question. If we hold x constant at some value n like you did in the video, would the non-recursive equation for f(x,y) always involve 2[n]y where [n] is the nth hyperoperation? (Except n=0, which would just be y[0] since the 0th hyperoperation only takes one input)

    • @FightingWolferine
      @FightingWolferine  Před 8 měsíci

      Apparently yes. Thanks for bringing this up. I previously didn't know the fact that this is actually the famous two-argument Ackermann function: en.wikipedia.org/wiki/Ackermann_function