python - Implement recursion using one recursive call -

given function follow : f(n) = f(n-1) + f(n-3) + f(n-4)

f(0) = 1 f(1) = 2 f(2) = 3 f(3) = 4 

i know implement using recursion 3 recursive calls inside 1 function. want 1 recursion call inside function. how can done ?

to implement using 3 recursive calls here code :

def recur(n):   if n == 0:      return 1   elif n == 1:      return 2   elif n == 2:      return 3   elif n == 3:      return 4   else:      return recur(n-1) + recur(n-3) + recur(n-4) #this breaks rule because there 3 calls recur 

your attempt in right direction needs slight change:

def main():   while true:     n = input("enter number : ")     recur(1,2,3,4,1,int(n))  def recur(firstnum,secondnum,thirdnum,fourthnum,counter,n):     if counter==n:      print (firstnum)      return   elif counter < n:       recur (secondnum,thirdnum,fourthnum,firstnum+secondnum+fourthnum,counter+1,n)