Mañjuśrī is the bodhisattva of wisdom, prajñā. He holds a flaming sword to cut through delusion in one hand, and the Perfection of Wisdom in 8,000 Lines Sutra in the other. His mantra is the first five letters of the Gāndhārī alphabet.
oṃ a ra pa ca na dhīḥ
अों अ र प च न धीः