(define (FUNO L)
    (cond   
        [(list? L)
            (cond
                [(empty? L) 1]
                [(equal? (length L) 1) (FUNO(first L))]
                [(* (FUNO(first L)) (FUNO (rest L)))]
            )
        ]
        [else L]
    )
)

(write(FUNO '(10 (8 (1) (1)) (20 (1) (1)))) ) #1600