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4 votes
4 answers
782 views

Bounding a binomial coefficient using the binary entropy function

I'm reading that recent paper on a new bound for diagonal Ramsey and am stuck at the attached "Fact 12.1", which is "standard". Could anyone please point me to a source for this ...
Lawrence Paulson's user avatar
1 vote
2 answers
165 views

A conjecture on 'truncated joint moments' of binomial coefficients under binomial distribution

This is similar in spirit to Sum of squares of middle binomial sums or 'Truncated mean' of binomial coefficients under binomial distribution but gives some total estimates. Though the other ...
VS.'s user avatar
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2 votes
1 answer
235 views

Sum of squares of middle binomial sums or 'Truncated mean' of binomial coefficients under binomial distribution

$\mu=1+\epsilon$ where $\epsilon>0$ holds. 1.Is there a good bound for $$T=\frac{\sum_{i=-\sqrt{\mu n\ln n}}^{\sqrt{\mu n\ln n}}\binom{n}{\frac n2 +i}^2}{2^n}?$$ This quantity can be ...
VS.'s user avatar
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2 votes
1 answer
147 views

Tight sublinear estimates for a triple partial binomial summation

Is there tight estimates for the following logarithmic summation ($\gamma,\gamma'\in(0,1)$ and $\mu,\mu'>0$) $$\log_2\Bigg(\sum_{t=\frac{n^{}}2-n^\gamma\sqrt{\mu\ln n}}^{\frac{n^{}}2+n^\gamma\sqrt{...
VS.'s user avatar
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0 votes
1 answer
163 views

Terminology and approximation to logarithm of a sum of products of binomial coefficients

Denote $$T(m)=\sum_{1\leq n_m\leq n_{m-1}\leq\dots\leq n_2\leq n_1\leq m}\prod_{i=1}^{m}\binom{n_i}{n_{i+1}}.$$ Is there a name for this kind of summation and is there a good estimate for $\ln T(m)$ ...
VS.'s user avatar
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0 votes
2 answers
208 views

Interpolating asymptotic expression for logarithm of middle binomial sums

Define $S(k,2n)=\sum_{i=-k}^k\binom{2n}{n+i}$ at every $k\in\{0,\dots,n\}$. We know $$\ln(S(\gamma\mbox{ } n^\gamma,2n))\asymp(2n\ln2-\frac12\ln\pi-\frac12\ln n)$$ at $\gamma\rightarrow0$ and $$\ln(S(...
VS.'s user avatar
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9 votes
3 answers
2k views

Asymptotics of multinomial coefficients

Binomial coefficients have a well known asymptotics (https://en.wikipedia.org/wiki/Binomial_coefficient#Bounds_and_asymptotic_formulas) given by $$\binom nk\sim\binom{n}{\frac{n}{2}} e^{-d^2/(2n)} \...
VS.'s user avatar
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