Răspuns :

2n+1 divide 60 , n∈N,

=> 2n+1∈D60

2n+1∈{1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60}  si n∈N

2n∈{0, 1, 2, 3, 4, 5, 9, 11, 14, 19, 29, 59} si n∈N

=> n∈{0, 1, 2, 7}