If. Sn = m * 3 ^ n + 1, then the real number M

If. Sn = m * 3 ^ n + 1, then the real number M

a1=s1=m*3+1=3m+1
a1+a2=s2=m*3^2+1
3m+1+a2=9m+1
a2=6m
a3=s3-s2=m*3^3-m*3^2=18m
Common ratio = A3 / A2 = 18m / 6m = 3
a2/a1=3
6m/(3m+1)=3
6m=3(3m+1)
m=-1