Finding L is like isolating L on the lefthand side (LHS) of the equation.

So you dispose off the negative part of the righthand side (RHS). Transpose it to the LHS.

Then, eliminate the barnacle 1.005301^n by dividing both sides of the new equation by 1.005301^n.

So L is isolated on the RHS.

Then, swap the positions so that the lonely L will be at LHS and the rest will be at the RHS.

Voila!

In my version,

L = [D_n +{p(1 -1.005301)^(n-1) / (1 -1.005301)}] / (1.005301^n)