If the sum of the first n terms of the sequence {an} is Sn and 3an = 3 + 2Sn, the general term formula of an is obtained
n=1 3*a1=3+2*a1 a1=3
2Sn=3An-3
2S(n-1)=3A(n-1)-3
Subtraction of two formulas
2An=3An-3-3A(n-1)+3
An=5/3A(n-1)
General term
When n = 1, A1 = 3
When n = < 2, an = [(5 / 3) ^ (n-1)] * 3
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