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    Okay so I've been staring at these two sequences for a while now and can't get anywhere:

    b) 5, 1, 2, 8, 8, 10, 9, 9, 2, 3, .....

    First one was solved

    I was hoping some genius on TSR could solve it and explain how.
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    (Original post by *Xena*)
    Okay so I've been staring at these two sequences for a while now and can't get anywhere:

    b) 5, 1, 2, 8, 8, 10, 9, 9, 2, 3, .....

    First one was solved

    I was hoping some genius on TSR could solve it and explain how.
    I'm gonna tag Zacken so he can move this to maths and possibly be of some assistance
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    (Original post by KaylaB)
    I'm gonna tag Zacken so he can move this to maths and possibly be of some assistance
    Ah, unfortunately I can't move it from this forum - not in my powers, it's not in study help. Sorry!

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    (Original post by *Xena*)
    Okay so I've been staring at these two sequences for a while now and can't get anywhere:

    b) 5, 1, 2, 8, 8, 10, 9, 9, 2, 3, .....

    First one was solved

    I was hoping some genius on TSR could solve it and explain how.
    Here's your sequence formula:

    \displaystyle 

\begin{align*}(a_n)_{n \in \mathbb{N}} &= \frac{409 n^9}{362880} \\ & -\frac{1129 n^8}{20160}\\ & +\frac{72199 n^7}{60480} \\&-\frac{20543 n^6}{1440} \\ &+\frac{1810021 n^5}{17280}\\ &-\frac{1401223 n^4}{2880}\\ &+\frac{128461229 n^3}{90720}\\ &-\frac{4128839 n^2}{1680}\\ &+\frac{142918 n}{63} \\ &-827\end{align*}

    Had to align it like that for it to fit. As to how? Look up Lagrange Interpolation.
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    (Original post by Zacken)
    Here's your sequence formula:

    \displaystyle 

\begin{align*}(a_n)_{n \in \mathbb{N}} &= \frac{409 n^9}{362880} \\ & -\frac{1129 n^8}{20160}\\ & +\frac{72199 n^7}{60480} \\&-\frac{20543 n^6}{1440} \\ &+\frac{1810021 n^5}{17280}\\ &-\frac{1401223 n^4}{2880}\\ &+\frac{128461229 n^3}{90720}\\ &-\frac{4128839 n^2}{1680}\\ &+\frac{142918 n}{63} \\ &-827\end{align*}

    Had to align it like that for it to fit. As to how? Look up Lagrange Interpolation.
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    (Original post by Zacken)
    Here's your sequence formula:

    Had to align it like that for it to fit. As to how? Look up Lagrange Interpolation.
    Did you do the algebra yourself? I typed it into Excel to find the differences, realised it was a 9th degree polynomial and decided to pretend I'd never seen the thread,
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    (Original post by 16Characters....)
    Did you do the algebra yourself? I typed it into Excel to find the differences, realised it was a 9th degree polynomial and decided to pretend I'd never seen the thread,
    Nah, just googled "Online Lagrange interpolate" and copy-pasted the TeX.
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    (Original post by Zacken)
    Nah, just googled "Online Lagrange interpolate" and copy-pasted the TeX.
    Ah, bless the internet.
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    (Original post by Zacken)
    Ah, unfortunately I can't move it from this forum - not in my powers, it's not in study help. Sorry!
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    (Original post by aymanzayedmannan)
    :rofl:
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    (Original post by Zacken)
    Here's your sequence formula:

    \displaystyle 

\begin{align*}(a_n)_{n \in \mathbb{N}} &= \frac{409 n^9}{362880} \\ & -\frac{1129 n^8}{20160}\\ & +\frac{72199 n^7}{60480} \\&-\frac{20543 n^6}{1440} \\ &+\frac{1810021 n^5}{17280}\\ &-\frac{1401223 n^4}{2880}\\ &+\frac{128461229 n^3}{90720}\\ &-\frac{4128839 n^2}{1680}\\ &+\frac{142918 n}{63} \\ &-827\end{align*}

    Had to align it like that for it to fit. As to how? Look up Lagrange Interpolation.
    How the **** is an A level student meant to get THAT?!
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    (Original post by *Xena*)
    How the **** is an A level student meant to get THAT?!
    I'm an A-Level student, 'innit
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    (Original post by Zacken)
    I'm an A-Level student, 'innit
    fml I would never have thought of Lagrange polynomials
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    (Original post by *Xena*)
    fml I would never have thought of Lagrange polynomials
    To be fair, there is some other descriptor of that sequence, but it's a crappy question and you can't define a unique sequence by giving an arbitrary number of terms, which makes me reluctant to even think about it beyond Lagrange.
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    (Original post by Zacken)
    To be fair, there is some other descriptor of that sequence, but it's a crappy question and you can't define a unique sequence by giving an arbitrary number of terms, which makes me reluctant to even think about it beyond Lagrange.
    So I guess I won't be getting into IBM
 
 
 
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