768=6(2)^n-1 then divide both sides by 6
128=2^n-1 then find a no. that will be the same base as 2 so...
2^7=2^n-1 then because n is unknown and the base is the same next transpose the 7. so it will become 7+1=n...8=n so 768 will be yhe 8th term.
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