posted by .

How many permutations σ of the set {1,2,…,15} are there such that σ(1)=1,∣σ(n)−σ(n−1)∣≤2 for 2≤n≤15?

Details and assumptions
σ(n) denotes the nth position of the permutation.

Similar Questions

1. Stor

Here is a simple way to create a random variable X that has mean μ and stan- dard deviation σ: X takes only the two values μ−σ and μ+σ, eachwith probability 0.5. Use the definition of the mean and …
2. Physics

A spherical shell of radius R carries a uniform surface charge density (charge per unit area) σ. The center of the sphere is at the origin and the shell rotates with angular velocity ω (in rad/sec) around the z-axis (z=0 …
3. Mathematics

Find the number of pairs of non-negative integers (n,m), such that 1≤n<m≤100, n∣m^2−1 and m∣n^2−1. Details and assumptions The notation a∣b means a divides b, or b=ka for some integer k.
4. Maths

Find the number of pairs of non-negative integers (n,m), such that 1≤n<m≤100, n∣m2−1 and m∣n2−1. Details and assumptions The notation a∣b means a divides b, or b=ka for some integer k.
5. Maths

We have 15 points {Ai} placed within the unit sphere. What is the maximum possible value of ∑1≤i<j≤15 ∣∣AiAj∣∣^2?
6. science

1 A ……... is a rectangular array of numbers that are enclosed within a bracket . horizontal set vertical matrix 2 When the numbers of rows is equal to the numbers of columns equal to 'n'. Where m=n. Then is called….. …
7. Materials Science

In this problem, you will construct the 2D Mohr's circle for two plane stress states defined in terms of the Cartesian components of the stress tensor in the x,y reference frame: [ σx,σy,τxy]. For each of these stress …
8. probability

Determine whether each of the following statement is true (i.e., always true) or false (i.e., not always true). 1. Let X be a random variable that takes values between 0 and c only, for some c≥0, so that P(0≤X≤c)=1. …
9. Calculus

Calculate μ and σ, where σ is the standard deviation, defined by the following. σ^2 = integral between (−∞,∞) (x-μ)^2 p(x) dx The smaller the value of σ the more tightly clustered are …
10. Calculus

Calculate μ and σ, where σ is the standard deviation, defined by the following. σ^2 = integral between (−∞,∞) (x-μ)^2 p(x) dx The smaller the value of σ the more tightly clustered are …

More Similar Questions