This is mantra of Sree Guru dattatrya,.,,,,,. Since it has no bjeeja it can be said without any initiation. .The Mantra is as follows
""DattTreya Hare Krishna unmatta Anandadayaka
Digambara mune Bala Pishacha Janna Sagara
  This contains 10 words. And it is most powerful.
Taken from Pravachan of shamukha sharma on Datta vybhava