New posts in discrete-mathematics

Venn diagram with rectangles for $n > 3$

How would I figure out how many anagrams of mississippi don't contain the word psi?

How do I know when to use nCr button and when to use nPr button on my calculator in which situation? [closed]

Negate and Simplify $p\wedge (q\vee r)\wedge(\neg p\vee\neg q\vee r)$

Integers $1, 2, \ldots, 10$ are circularly arranged in an arbitrary order. [duplicate]

How to find non-isomorphic trees?

How is the relation "the smallest element is the same" reflexive?

Theory of definitions

Prove two sets have same Cardinality by writing down bijection

Any $B \subset \{10,11,...,99\}$, with $|B| =10$ has two subsets such that $\sum_{a \in B_1} a = \sum_{b \in B_2} b$

Fibonacci numbers divisible by $9$

Explicit solution of the recursion $x_n = x_{n-1}^2 - 2$ with $x_0>2$

Graph with even vertices and ${n-1}\choose 2$ $+ 1$ edges has a perfect matching

How to start proving $A \times B \times C \ne (A \times B) \times C$?

Proving for all integer $n \ge 2$, $\sqrt n < \frac{1}{\sqrt 1} + \frac{1}{\sqrt 2}+\frac{1}{\sqrt 3}+\cdots+\frac{1}{\sqrt n}$ [duplicate]

How many bit strings of length 8 start with "1" or end with "01"?

Hint for problem on $4 \times 7$-chessboard problem related to pigeonhole principle

Chromatic Polynomial

Prove $\sum_{k= 0}^{n} k \binom{n}{k} = n \cdot 2^{n - 1}$ using the binomial theorem

Find the number of ways to express 1050 as sum of consecutive integers