Generating Functions and Combinatorial Identities

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  • เผยแพร่เมื่อ 26 ธ.ค. 2024

ความคิดเห็น • 16

  • @jamesfortune243
    @jamesfortune243 3 ปีที่แล้ว +2

    Generating functions are already powerful on their own. Your restrictions to multiples and extensions to partitions (different video) have made them even more general and powerful.

  • @kazebaret
    @kazebaret 4 ปีที่แล้ว +10

    Amazing video.... The only thing I do not understand is why you have only 24.4 K subscribers, instead of their number tending to infinity....

    • @tomatrix7525
      @tomatrix7525 3 ปีที่แล้ว +4

      It’s ok, Michael finally reindexed the sum so he has 100,000 subs

    • @pbj4184
      @pbj4184 3 ปีที่แล้ว +1

      @@tomatrix7525 A further 35k now!

  • @Alex-ri6be
    @Alex-ri6be 5 ปีที่แล้ว +4

    Great, a new video on generating functions! 🙂

  • @mackenziekelly1148
    @mackenziekelly1148 3 ปีที่แล้ว

    Around 18:30 they should have been positive etas since you were multiplying -x^(1/3) by itself but they still would have added to zero so you still got the answer.

  • @dugong369
    @dugong369 4 ปีที่แล้ว

    It looks like the F(3n) series converges for abs(x) < phI^-3 = sqrt(5) - 2 which is about .236, which makes sense as phi^3 would be the limiting ratio of every third term of the Fibonacci sequence.

  • @pjk9681
    @pjk9681 3 ปีที่แล้ว

    Many thanks. Is there a video on the "way" to determine a generating function, as that would be helpful indeed?

  • @behzat8489
    @behzat8489 2 ปีที่แล้ว

    with this method we obtained a formula for a_(3n), what about a_(3n+1)? any ideas?

    • @peterirvin7121
      @peterirvin7121 ปีที่แล้ว +2

      You could maybe shift the generating function to the left and re-do the original procedure.
      i.e. start with A_n(x) --> A_n(x)/x

  • @tomatrix7525
    @tomatrix7525 4 ปีที่แล้ว +1

    Wow, these gemerators are crazy

  • @d-rex7043
    @d-rex7043 3 ปีที่แล้ว

    ... this was the vid I was supposed to be watching!

  • @rekolitafotiro
    @rekolitafotiro 4 ปีที่แล้ว

    I have a question, if someone could help me give it an answet I´d be grateful. If you have a generating function, for example, for the positive integers (1/(1-x)^2), could you substitute that in the formulas given in this video to obtain the generating functions of the multiples of 2 or any other natural number? Thanks in advance for the answer

    • @xCorvus7x
      @xCorvus7x 3 ปีที่แล้ว +1

      Since that part was general, did not depend on any property of the Fibonacci numbers or their generating function, you can use complex roots as coefficients to get any subsequence of a sequence whose generating function you already have.
      Notice how in the beginning he mentioned that he only chose the Fibonacci numbers and their generating function because he likes the Fibonacci numbers.

  • @fasihullisan3066
    @fasihullisan3066 4 ปีที่แล้ว

    thanks

  • @LucaIlarioCarbonini
    @LucaIlarioCarbonini 4 ปีที่แล้ว

    Good news: I'm not the only one who love these kind of toys.
    Bad news: my result (for F_kn over a^n to find the minimum real a while keep convergence) does not match your... and I believe your...
    D'OH!