I am running VNS algorithm from MEIGOR in R to solve the classic optimization problem "Traveling Salesman Problem (TSP)". The algorithm are working well, but in my results it is possible to identify some repetition of nodes (eg.: 3; 5; 8; etc.). Please, note the output bellow:

Best solution value 22681.46 Decision vector 17 29 5 48 51 37 49 4 16 40 9 44 8 6 3 3 13 28 22 19 12 30 32 41 46 23 21 38 50 11 25 26 38 44 31 15 45 49 36 43 20 34 39 33 43 8 23 35 5 48 10 18

Thus, I would like to ask wich parameter i have to use to avoid repetition in my decision Vector?