User:IssaRice/Summary of counting techniques: Difference between revisions

Revision as of 02:12, 14 August 2019

Let $A$ be a set with $n$ elements, and let $B$ be a set with $m$ elements.

Description	Set representing counting problem	number of ways to count
	${(a_{1}, \dots, a_{k}) : a_{1}, \dots, a_{k} \in A}$
	${{a_{1}, \dots, a_{k}} : a_{1}, \dots, a_{k} \in A}$
	${(a_{1}, \dots, a_{k}) : a_{1}, \dots, a_{k} \in A and all a_{i} distinct}$
	${{a_{1}, \dots, a_{k}} : a_{1}, \dots, a_{k} \in A and all a_{i} distinct}$
	${(a, b) : a \in A and b \in B}$

@@ Line 6: / Line 6: @@
 | || <math>\{(a_1, \ldots, a_k) : a_1,\ldots, a_k \in A\}</math> ||
 |-
-| || <math>\{{a_1, \ldots, a_k} : a_1,\ldots, a_k \in A\}</math> ||
+| || <math>\{\{a_1, \ldots, a_k\} : a_1,\ldots, a_k \in A\}</math> ||
 |-
 | || <math>\{(a_1, \ldots, a_k) : a_1,\ldots, a_k \in A \text{ and all }a_i\text{ distinct}\}</math> ||