Substitution resolution function? b=0.8？ k=0.2

So An is on y=0.2x+0.8.

Let A3(p, 0.2p+0.8)

When A3 is taken as the vertical line of the x axis, the equation can be obtained.

0.2p+0.8 = p-(2 * 1+2 * 1.5)

The solution is p=7.25.

So A3(7.25, 2.25)

Observe OB 1=2=2* 1? (i.e 2 * 1 * 1.5 0)?

OB2=3=2*( 1.5？ )^ 1

OB3=4.5=2*( 1.5)^2

So OBN = 2 * (1.5) (n- 1)

So the ordinate of An is 1.5 (n- 1).

Substitute y=0.2x+0.8? x=5* 1.5^(n- 1)-4

an( 1.5^(n- 1),5* 1.5^(n- 1)-4)