sicp-ex-5.29

  
  
 (a) 
 n   total-pushes    maximum-pushes 
 1         18                       11 
 2         78                       19 
 3        138                      27 
 4        258                      35 
 5        438                      43 
 the maximu-pushes is: 8n + 3 
 (b) 
 S(n) = S(n-1) + S(n-2) + 42 
 S(n) = 60Fib(n+1) - 42