Episode #125 of the Stack Overflow podcast is here. We talk Tilde Club and mechanical keyboards. Listen now
pi66

### Questions (159)

 28 Prove $|P(0)|\leq 2n+1$ 26 Parts with the maximum number of each integer 18 Partition of 4-tuples 17 Sum of roots rational but product irrational 14 Dividing books between two couples

### Reputation (4,026)

 +10 Suppose $M$ is an $m \times n$ matrix such that all rows and columns of $M$ sum to $1$. Show that $m=n$ +5 Expected value of maximum of i.i.d. random variables +30 Infinite cube and divisible sums +5 Disjoint sets with twice ratio

 29 Suppose $M$ is an $m \times n$ matrix such that all rows and columns of $M$ sum to $1$. Show that $m=n$ 26 Is there a simple function that generates the series; $1,1,2,1,1,2,1,1,2…$ or $-1,-1,1,-1,-1,1…$ 13 very basic question about coordinate geometry 10 What is the maximum even number that can not be expressed as sum of two composite odd numbers? 10 $m+n$ divides $a_m+a_n$

### Tags (120)

 58 linear-algebra × 12 29 invariance 51 number-theory × 8 27 exponentiation × 3 44 sequences-and-series × 15 26 functions × 4 36 combinatorics × 60 25 elementary-number-theory × 27 35 matrices × 2 19 algebra-precalculus × 36