C# Construct Line Links Over Time

I'm trying to make script where when gameObject enters another gameObject's Physics.OverlapSphere the gameObject adds it to gos and create line links between a series of gameobjects within each gameobjects Physics.OverlapSpheres. I've added the scripted gameobject to gos so gos wouldn't be null but the aren't being created. Is there something wrong with the logic of my script?

 using UnityEngine;
 using System.Collections;
 using System.Collections.Generic;
 public class LaserZigZag : MonoBehaviour {
 public List<GameObject> gos = new List<GameObject>();
     public Collider[] cols;
     // Use this for initialization
     void Start () {
     
     }
     
     // Update is called once per frame
     void Update() {
                     for (int i = 0; i < gos.Count -1; i++){
                         cols = Physics.OverlapSphere(gos[i].transform.position, 5f);
                         if(cols[i+1].gameObject == gos[i]){
                             gos.Add(cols[i+1].gameObject);
                         }
                     }                
     
         for (int i = 0; i < gos.Count -1; i++)
             if (Physics.Linecast(gos[i].transform.position, gos[i+1].transform.position)){
                 Debug.DrawLine(gos[i].transform.position, gos[i+1].transform.position, Color.red);
             }    
     }
 }