# A little math problem

#### Informatix

##### Expert
Longtime User
Hello,

Is there a way to solve this problem easily ?
I want to find the initial increment for a mathematical serie of n values. All series have to go from 0 to 1.

With 3 values, for example, the initial increment is 0.3333333:
First value = 0 + (0*0.333333) = 0
Second value = first value + (1*0.333333) = 0.33333333
Third value = second value + (2*0.3333333) = 1

With 4 values, the initial increment is 0.1666666:
First value = 0 + (0*0.1666666) = 0
Second value = first value + (1*0.1666666) = 0.1666666
Third value = second value + (2*0.1666666) = 0.5
Fourth value = third value + (3*0.1666666) = 1

A big like for any answer helping to solve that problem without using brute force.

#### udg

##### Expert
Longtime User
Hi Informatix,

it looks like that to compute x (0.1666..) you should simply divide 1 by the series (n * n-1)/2 that is the one which gives you the sum of n natural numbers.
Is that what are you after?

udg

#### Informatix

##### Expert
Longtime User
Yes, thanks a lot.
I'm back from vacation and my brain is like mud.