Jul 21, 2016 · Stack Exchange Network. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for …

For example, $3 \cdot 3 =1$ correct? $3$ couldn't be the generator because if I kept doing this operation I would start repeating the same elements, but not all the elements ($1,3,5,7)$ …

Nov 22, 2015 · The main idea is that we can use the cycle $\sigma^{-1}$ to "shift up" the numbers which we are permuting so that the pair that we want to transpose end up in the $1$ and $2$ …

For one, be careful with the phrase "a principal ideal generated by two elements". An ideal is principal by definition if it is generated by a single element. In certain rings, such as $\mathbb …

1) What does it mean by stabilisers of 3 different bijections of {1,2,3,4}? Is that to say the elements of S4 which send {1,2} and {3,4} to {1,2},{3,4} i.e. by (12)(34)? 2) How does he know …

Jul 22, 2013 · Bases and subbases "generate" a topology in different ways. Every open set is a union of basis elements. Every open set is a union of finite intersections of subbasis elements. …

Jul 8, 2017 · On a set n elements, the matrix is a square matrix with n rows & n columns (where each element corresponds to an ordered pair of elements from the set). Make the following …

A set of $4$ elements has $2^4$ subsets. These include the empty set, in which case you eat nothing. So the answer is $16$ if eating nothing is an option, or $15$ if eating nothing is not an …

Jan 27, 2015 · Stack Exchange Network. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for …

Aug 20, 2014 · Stack Exchange Network. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for …