You may be asking for both: Navkar (Namokar) Mantra and the Logassa (Logassa/Logasā) Sutra. Here are both, with simple, traditional meanings.

1) Navkar (Namokar) Mantra Prakrit (traditional form)

• Namo Arihantanam
• Namo Siddhanam
• Namo Ayariyanam
• Namo Uvajjhayanam
• Namo Loe Savva-sahunam
• Eso panch namokkaro, savva-pavappanasano
• Mangalanam cha savvesim, padhamam havai mangalam

Arth (simple meaning)

• I bow to Arihants (perfect beings with kevaljnan).
• I bow to Siddhas (liberated souls).
• I bow to Acharyas (head monks).
• I bow to Upadhyays (scripture-teachers).
• I bow to all Sadhus-Sadhvis in the world.
• This five-fold obeisance destroys all karmic demerit and is the foremost auspicious mantra.

For a clear, beginner-friendly reference:

2) Logassa Sutra (Chaturvimsati-stava) – Śvetāmbara text Prakrit (seven gāthās, as preserved in Avashyaka/Pratikraman):

• Logassa ujjoa-gare, dhamma-tittha-yare jine

Arihante kittaissam, chauvisam pi kevali 1

• Usabha-majiam cha vande, sambhava-mabhinandanam cha sumaim cha

Paumappaham supasam, jinam cha chanda-ppaham vande 2

• Suvihim cha puppha-dantam, siala-sijjamsa-vasu-pujjam cha

Vimala-manantam cha jinam, dhammam santim cha vandami 3

• Kunthum aram cha mallim, vande muni-suvvayam nami-jinam cha

Vandami rittha-nemim, pasam taha vaddhamanam cha 4

• Evam mae abhithua, vihuyara-mala pahina-jara-marana

Chauvisam pi jinavara, tittha-yara me pasiyantu 5

• Kittiya-vandiya-mahiya, je e logassa uttama siddha

Arugga-bohi-labham, samahi-vara-muttamam dintu 6

• Chandesu nimmala-yara, aichchesu ahiyam payasa-yara

Sagara-vara-gambhira, siddha siddhim mama disantu 7

Arth (simple meaning)

• I praise the 24 Kevalis (Tirthankaras) who illumine the world and establish the dharma-tirtha.
• I bow sequentially to the 24 Tirthankaras: Rishabh through Mahavir.
• May these Jinas, free from karmic stains and beyond old age and death, be gracious to me.
• I revere the Siddhas, purer than the moon, brighter than the sun, deeper than the ocean; may they grant true samadhi and spiritual attainment.

Reference with full text and meaning:

Notes on traditions

• Śvetāmbara: Recites Logassa as above (part of daily Avashyaka/Pratikraman).
• Digambara: An equivalent Tirthankara-stuti is popularly recited (often beginning “Thossi mi…”); wording differs, but the devotion is the same—obeisance to the 24 Tirthankaras and Siddhas. The Navkar (Namokar) Mantra lines are common to both, with only minor pronunciation/spelling variations (e.g., Loe/Loya; Savva/Sabba).

Both prayers preserve the Jain essence: bowing to गुण (virtues) of the Panch Parameshthi and the 24 Jinas, seeking inner purity and liberation, without asking for material favors.