Three terms of an arithmetic sequence are shown below. Which recursive formula defines the sequence? f(1)= 6, f(4) = 12,f (7) = 18
f(n +1 ) =f(n) +6
f(n +1 )=2 f(n)
f(n +1) = f (n) +2
f(n + 1) = 1.5f(n)
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