Find the number of distinct arrangements of 5 unequal positive integers such that their sum is 20
47550
Number of distinct arrangements {$n_i$} $n_1<n_2<n_3<n_4<n_5$ such that $\sum n_i=20$
101758
combinatorics circular arrangement problem
112575
Finding integer solutions of $m^2-n^5 = m - n$
58103
number of permutations in which no two consecutive numbers are adjacent
104010
The number of partitions of $n$ into distinct parts equals the number of partitions of $n$ into odd parts
132175
How many $5$-digit numbers with distinct digits are divisible by 3 (and generalize)
158124
Sum of all the positive integers problem
144779
The number of ways to represent $(n^2+n)/4$ as a sum of $n/2$ distinct integers in $1,\dots,n$
65764
Partitioning $\{1,2,\ldots,k\}$ into $p$ subsets with equal sums, where $p$ is prime
20443
Calculate sum of squares of first $n$ odd numbers
72857
Find the number of integral solutions of $2x + y + z = 20$?
142477
Closed-form expression for the number of $k$-permutations of length $n$. Duplicates allowed!
116251
Number of distinct total orders on a set
143501
Find all $n\in\mathbb N^+$ such that the sum of the digits of $5^n$ is equal to $2^n$.
142978
combinatorics: sum of product of integer compositions
60847
What three odd integers have a sum of 30?
14687
Is it possible to easily count all the possible distinct sums from distinct numbers?