Martín-Blas Pérez Pinilla

 111 What are some counter-intuitive results in mathematics that involve only finite objects? 44 What's your favorite proof accessible to a general audience? 42 What are the applications of functional analysis? 40 Limit of sequence in which each term is defined by the average of preceding two terms 38 How could we define the factorial of a matrix?

### Reputation (36,640)

 +10 Simple theorems that are instances of deep mathematics +10 In analytic proofs of the hairy ball theorem +45 Show that $\sum_{k=1}^\infty a_k=\sum_{k=1}^\infty a_{2k} +\sum_{k=1}^\infty a_{2k-1}$ +10 Why does the Riemann sum of a double integral use $\Delta x, \Delta y \rightarrow 0$ as its limit instead of $m,n \rightarrow \infty$?

### Questions (2)

 1 Intuition for formula in proof of Poincaré Lemma 0 Zero sharp and Kunen inconsistence.

### Tags (431)

 420 calculus × 304 248 limits × 121 388 real-analysis × 279 244 sequences-and-series × 151 307 soft-question × 54 167 linear-algebra × 101 282 big-list × 36 139 integration × 125 264 complex-analysis × 185 139 reference-request × 34