var letters = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ") func randSeq(n int) string { b := make([]rune, n) for i := range b { b[i] = letters[rand.Intn(len(letters))] return string(b) func main() { fmt.Println(randSeq(6))