(define (Hn n )
  (define half_arg (/ n 2.0))  

(define (series_sum n)
  (if (=  n half_arg ) 0 
    (+ (/ 1.0  n) (series_sum(- n 1)) )
  )  
 )
 (series_sum n)   )

(writeln (Hn 4))
(writeln (Hn 8))
(writeln (Hn 16))
(writeln (Hn 32))
(writeln (Hn 64))
(writeln (Hn 128))
(writeln (Hn 256))
(writeln (Hn 512))
(writeln (Hn 1024))
(writeln (Hn 2048))
(writeln (Hn 4096))