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0 votes
1 answer
54 views

Formula for number of monotonically decreasing sequences of non-negative integers of given length and sum?

What is a formula for number of monotonically decreasing sequences of non-negative integers of given length and sum? For instance, if length k=3 and sum n=5, then these are the 5 sequences that meet ...
JacobEgner's user avatar
0 votes
2 answers
65 views

Number of positive integral solution of $\sum_{i=1}^{10} x_i=30,\text{ where } 0 < x_i<7, \forall 1\le i\le 10$

I want to find the number of positive integer solutions of the equations given by $$\sum_{i=1}^{10} x_i=30,\text{ where } 0 < x_i<7, \forall 1\le i\le 10.$$ I know the case that, for any pair of ...
abcdmath's user avatar
  • 1,707
2 votes
2 answers
171 views

Number of ways to complete a partial Young tableau

Suppose we have a Young tableau with missing entries. Then there can be many number of ways we can complete the Young Tableau. Is there any specific method to find the number of ways we can complete a ...
user5210's user avatar
  • 399
3 votes
1 answer
120 views

Conjugate of conjugate partition

Let $\lambda=(\lambda_1,\dots,\lambda_r)$ is a partition of $n$ and denote $\lambda'$ the conjugate partition of $\lambda$, with $\lambda'_j=\#\{i\,|\,\lambda_i\ge j\}$. I'm struggling to try to prove ...
FreeFunctor's user avatar
3 votes
1 answer
79 views

Sum of integers closest to a given number

I have the following problem at hand: Given an odd number $n > 7$, find a set of non-negative integers $m_7$, $m_8$, ..., $m_{13}$ and $m_{14}$, such that the sum $m_7\cdot 7 + m_8\cdot 8 + ... + ...
Ubuntu_fan's user avatar
5 votes
2 answers
412 views

Maximizing product of three integers

It is well-known that, if we want to partition a positive number $m$ into a sum of two numbers such that their product is maximum, then the optimal partition is $m/2, ~ m/2$. If the parts must be ...
Erel Segal-Halevi's user avatar
2 votes
1 answer
93 views

Divide an integer in the sum of two integers with percentage factor using ceil and floor

I have encoutered a problem in a software that I use for invoicing. I have a variable (quantity) integer A which I want to split in a sum of two integers using a percentage p where $A1 = p*A$ and $A2 =...
marz's user avatar
  • 21
2 votes
1 answer
96 views

2-split of $n$ is $\left\{ \lfloor \frac{n}{2} \rfloor,\lceil \frac{n}{2} \rceil \right\}$. What about 3, 4, ...?

Clarification: $k$-split of $n$ is an ordered integer sequence $\left\{ a_1,\cdots,a_k \right\}\quad \text{s.t.}$ $0\le a_1\le\cdots\le a_k$ $a_1+\cdots+a_k=n$ ${\left(a_k-a_1\right)}$ is minimized. ...
SnzFor16Min's user avatar
1 vote
0 answers
42 views

Algorithm to find the distinct representations of the integer $n$ as a sum of $k$ non-negative p^(th) integer powers.

I am a user of Wolfram Mathematica and in that software there is a function called: PowersRepresentations. This function returns lists of integers $0\le n_1\le n_2\le\dots\le n_k$ such that $n_1^p+n_2^...
Putjul's user avatar
  • 21
3 votes
0 answers
44 views

By which scheme should I add the elements in series $(\sum n^{-2})^2$ and $\sum n^{-4}$ to show their rational equivalence?

We know that $\sum n^{-2}=\frac{1}{1^2}+\frac{1}{2^2}+\frac{1}{3^2}+\dots=\frac{\pi^2}{6}$ and $\sum n^{-4}=\frac{1}{1^4}+\frac{1}{2^4}+\frac{1}{3^4}+\dots=\frac{\pi^4}{90}$ from "high mathematics" ...
sanaris's user avatar
  • 253
0 votes
0 answers
20 views

Find minimum integer such that any integer \in [1, n] can be constructed from its consequent subsums

For example, here's (SPOILERS) breakdown for $1143$, which is the solution for $n = 9$ $\underline{1}143$ $\underline{11}43$ $114\underline{3}$ $11\underline{4}3$ $1\underline{14}3$ $\underline{114}3$...
kirilloid's user avatar
  • 230
1 vote
1 answer
91 views

Lower bound on sum of integer vectors

Given 2 integer vectores (add zeros to shortest if necessary) we can sum them term by term to get a new integer vector. $$ (1,2,3) , (1,5,7) $$ If we add the possibility to permute components from ...
24th_moonshine's user avatar
0 votes
2 answers
223 views

Expressing a positive integer as a sum of 3 positive integers

Let us denote the the number of ways in which a positive integer, $n$, can be expressed as a sum of $3$ positive integers (not necessary distinct) by $W_3(n)$. $W_3(n)$ can be evaluated using any of ...
Hussain-Alqatari's user avatar
0 votes
2 answers
245 views

To prove identity $P(n,3)= \lfloor n^2/12 \rfloor$

Suppose $P(n,k)$ is number of partitions of positive integer n by k positive integers with no duplicative tuples. And $\lfloor r\rfloor$ is largest of integers equal or less than real number $r$ If $...
Solvable Potato's user avatar
2 votes
2 answers
90 views

How many compositions does 40 have (with up to 5 addends), with each positive integer addend between 2 and 12?

I was on Youtube and found a show called Monopoly Millionaires' Club. I thought it would be interesting to try to calculate the probability of winning the million dollars. The contestant starts on ...
August's user avatar
  • 1,562

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