How do I add Additive Noise into a sequence of number,C#?

I am beginner in C#. How do i add Additive Noise into a sequence of number? For example, I want to add Noise(3,2,1) into this sequence:

1:1
2:1
3:1
4:1
5:2
6:1
6:2
6:60
7:1
8:1
9:2
10:1

The expected result are as follows, where the noise will be added randomly.

1:1
2:1
3:1
4:1**,3**
5:2
6:1
6:2
6:60**,2**
7:1
8:1
9:2**,1**
10:1