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emdiesse · Mar 9th, 2008, 6:17 PM

Hello. I am attempting to use recursion to output the sequence of numbers 2, 3, 7, 13, 27, 53, ...

public class TDSeq {
   private static int printSequence(int F, int k) {
      if(k ==1) return 2;
      if(k ==2) return 3;
      F = printSequence(F, k-1)  + (2*printSequence(F, k-2));
      System.out.print(F + ", ");
      return F;    
   }
    
   public static void main(String[] args) {
      int k = 8;
      int F = 3;
      printSequence(F, k);
   }  
}

Now this give a horrible output:
7, 13, 7, 27, 7, 13, 53, 7, 13, 7, 27, 107, 7, 13, 7, 27, 7, 13, 53, 213,

No where near the aim of:

2, 3, 7, 13, 27, 53, ...

Now I really can't get my head around this, however I would really like to learn how to use recursion effectively.

Any one got any help or advice they can offer?

Mar 9th, 2008, 6:17 PM	#1
emdiesse Programmer Join Date: Jul 2004 Location: Hampshire Posts: 56 Rep Power: 5	Recursion to compute sequences. Hello. I am attempting to use recursion to output the sequence of numbers 2, 3, 7, 13, 27, 53, ... (Toggle Plain Text) public class TDSeq { private static int printSequence(int F, int k) { if(k ==1) return 2; if(k ==2) return 3; F = printSequence(F, k-1) + (2printSequence(F, k-2)); System.out.print(F + ", "); return F; } public static void main(String[] args) { int k = 8; int F = 3; printSequence(F, k); } } public class TDSeq { private static int printSequence(int F, int k) { if(k ==1) return 2; if(k ==2) return 3; F = printSequence(F, k-1) + (2printSequence(F, k-2)); System.out.print(F + ", "); return F; } public static void main(String[] args) { int k = 8; int F = 3; printSequence(F, k); } } Now this give a horrible output: 7, 13, 7, 27, 7, 13, 53, 7, 13, 7, 27, 107, 7, 13, 7, 27, 7, 13, 53, 213, No where near the aim of: 2, 3, 7, 13, 27, 53, ... Now I really can't get my head around this, however I would really like to learn how to use recursion effectively. Any one got any help or advice they can offer?