Please provide detailed step-by-step solutions! Will give thumb-up for good answer. Thank you!

1. The function f(n) is defined for positive integers n by the following recursive program: if (nl) then return(2) else if (n--2) then return (3); else return(2*f (n-2) -f (n-1)) Compute f(12), f(13), f(14), and f(15). Then, identify one of the correct values from the list below. Note: it is not necessary to simulate fexactly as written. a) f(15) =-8191 b) f(12) 1025 e c) f(14)-13,653 e d) f(15)-5459