The hardest task I have ever faced in my HSC (1 Viewer)

DarkOperator618

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Original Poster said:
I have chosen The Catalan numbers

So I go on this OEIS website, to find a bunch of code language that I understand nothing of. It’s like it’s another language entirely.
So I was able to get the name of sequences being the Catalan numbers, I’m assuming the first few terms are the ones shown in the website.
But as for for the recurrence relation, I got nothing.
I think I should be able of going the others, but when I google the recurrence thing I still don’t understand it.
So what do I write for the recurrence relation?

3D9A6F38-D746-456F-8C3E-EDA2D375DF81.jpeg
what is this lmao

That looks disgusting

Our assignment was literally something related to stats and probability
 

Qeru

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The reccurence relation is : where is the kth catalan number.

The general term is:

where means 2n 'choose' n. It may be worthwhile looking into some basic combinatorics i.e. permutations and combinations particularly what a factorial is.

Also learn how to use google better (I literally googled everything in this answer).
 

jimmysmith560

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Kind of unrelated, but is anyone else intrigued by how much 2U maths has changed, or is it just me? I mean, what are those assignments and parentheses lol 😅
 

AKONS

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Kind of unrelated, but is anyone else intrigued by how much 2U maths has changed, or is it just me? I mean, what are those assignments and parentheses lol 😅
Yeah Im just as confused as you! Although I think this is because of teacher preferences. At my school the teachers would just assess is with a math exam like the hsc. But I guess theres a lot of leniency in how u assess students :/
 

Qeru

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Kind of unrelated, but is anyone else intrigued by how much 2U maths has changed, or is it just me? I mean, what are those assignments and parentheses lol 😅
You did 3U right? The 'parantheses' is simply a combination
 

Etho_x

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Kind of unrelated, but is anyone else intrigued by how much 2U maths has changed, or is it just me? I mean, what are those assignments and parentheses lol 😅
The advanced cohort at my school have to do something on the Rule of 72 for GP's and finance lol. Advanced assignments are so weird -.-
 

jimmysmith560

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The advanced cohort at my school have to do something on the Rule of 72 for GP's and finance lol. Advanced assignments are so weird -.-
That's pretty cool. The rule of 72 was part of a compulsory core finance unit I did in my first year at uni.
 

jimmysmith560

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most learn perms and combs in y11
Yeah we did perms and combs. It's just that I don't remember learning/using that type of notation (the parentheses bit). 🤷‍♂️

lol vid is 19 mins long yet reply is in 6 mins
Oh haha I've seen his channel before but never got a chance to give a positive comment. I'm already familiar with the rule of 72.
 

Qeru

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Yeah we did perms and combs. It's just that I don't remember learning/using that type of notation (the parentheses bit). 🤷‍♂️



Oh haha I've seen his channel before but never got a chance to give a positive comment. I'm already familiar with the rule of 72.
fair enough
 

cossine

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But when I google the recurrence thing I still don’t understand it.
Think of function when a function is reused to calculate the value of it argument your dealing with recursive function
e.g.

Let say we have function call fibonacii(n) where n is the nth term. The output of fibonacii(n) is the nth term of the fibonacii sequence.

fibonacii( nth_term) = fibonacii(n-1th_term) + fibonacii(n-2th_term)

You could look at some programming books if you wanted to or perhaps a discrete math textbook but it is a overkill.
 

username_2

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you know when you have something like this the first thing you search is Catalan numbers and you get a wiki page. Yeh. Go through it first - link: https://wiki2.org/en/Catalan_number

Dont be super intimidated by it.

Recurrence relation - when I have a sequence where I know n number of terms and the n+1 term is dependent upon the previous n terms.. For example: if I want my initial numbers in the sequence to be 0 and 1, then what I would do is define a rule (which is the recurrence formula) to generate a sequence.

So let the rule be that the next term will be the sum of the previous two terms (which is a form of the Fibonacci sequence). TO write this rule mathematically, we get the following rule:
Term (n) = Term (n-1) + Term (n-2)
Term (3) = Term (2) + Term (1) = 0 + 1 which is 1

from here you do the research. It is your assignment.
 

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