n=1(1xn)24 \displaystyle \prod_{n=1}^{\infty} (1-x^n)^{24} coefficients

P(x)=n=1(1xn)24 P(x) = \displaystyle \prod_{n=1}^{\infty} (1-x^n)^{24}

"Unwrapping" the product, you get a polynomial with coefficients anR a_n \in \mathbb{R} :

P(x)=a0+a1x+a2x2+... P(x) = a_0 + a_1 x + a_2 x^2 + ...

Prove whether or not there exists a coefficient an=0 a_n = 0 in this polynomial. This is a problem I've been attempting to solve for over a week now but have made no significant progress on after turning the product (without the 24th power) into an infinite series. Could anyone offer some insight, please?

#NumberTheory

Note by Arsenii Zharkov
10 months, 3 weeks ago

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So far I think my most significant progress has been getting it into the form n=1(1xn)24=n=(1)nx3n2n2 \displaystyle \prod_{n=1}^{\infty} (1-x^n)^{24} = \sum_{n=-\infty}^{\infty} (-1)^n x^{\frac {3n^2-n}{2} }

Arsenii Zharkov - 10 months, 3 weeks ago

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If the statement you said thatP(x)=a0+a1x+a2x2+a3x3+....P(x)=a_0+a_1x+a_2 x^2+a_3 x^3+.... then , P(0)=a0,(ddxP(0))=a1,(d2dx2P(0)2!)=a2,...P(0)=a_0,(\frac{d}{dx}P(0)) =a_1 ,(\frac{d^2}{dx^2}\frac{P(0)}{2!}) =a_2,...and so on. So if any ana_n to be zero the derivative of the product defined at zero must be zero.This is my insight and I hope you will get some idea , personal I feel it won't have a zero coefficient.

Aruna Yumlembam - 10 months, 3 weeks ago

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Here due to my bad knowledge of latex the derivative of the product has to be calculated first then put x=0.It's a pretty good question has many applications.

Aruna Yumlembam - 10 months, 3 weeks ago

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@Aruna Yumlembam Plus the basic idea is using the Taylor series expantion,to denote the coefficient.

Aruna Yumlembam - 10 months, 3 weeks ago

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@Aruna Yumlembam Unfortunately I haven't managed to find a good way to take the derivative of the function, but I did figure out the first 5 coefficients using combinatorics. For x, there's 24 "blocks" to choose from, For x^2, either 24 x^2's to choose from or 24 x's to choose 2 of from, etc., but I've been struggling with coming up with any form of general formula that actually confirms the absence of an an=0a_n=0

Arsenii Zharkov - 10 months, 3 weeks ago

@Zakir Husain

Yajat Shamji - 10 months, 3 weeks ago

@Gandoff Tan

Yajat Shamji - 10 months, 3 weeks ago

@Neeraj Anand Badgujar

Yajat Shamji - 10 months, 3 weeks ago

@Aruna Yumlembam

Yajat Shamji - 10 months, 3 weeks ago

@Naren Bhandari

Yajat Shamji - 10 months, 3 weeks ago
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