In how many ways can $4$ books be removed from a bookshelf with $15$ books such that no two adjacent books are chosen?
34452
In how many ways can you choose $k$ numbers out of $\{1,2,3,\dots,n\}$ so none of them is consecutive?
145102
Selecting A combination of minimum cost
82828
Double-blind review with four references in a row?
14609
How many ways "ARRANGE" can be arranged?
76405
Let n be an even integer. How many different ways can I choose subsets of the set {1,2...,n}
9411
Number of permutations of $n$ elements where no number $i$ is in position $i$
97265
count the ways to fill a $4\times n$ board with dominoes
28903
Replace or remove bibliography numbers
108275
How do I count the subsets of a set whose number of elements is divisible by 3? 4?
150281
Am I on the right track to figure out this combinatorics problem?
29238
Making Change for a Dollar (and other number partitioning problems)
9850
How many ways are there to choose 3 subsets $A,B,C$ of a set $\{1,2,3...n\}$ such that $ A \cap B \cap C = \emptyset $
142180
There are 'n' candies and 't' boxes. Find the number of ways to place the candies in the boxes for each of the conditions (given in the problem).
107964
Simple combinatorics problem.
68636
Remove blank pages in twosided book class without openany
25457
FreeCell: How many cards can be moved at once?
73497
Getting rid of numbers