In Jainism, "Trivihar Upvaas" refers to a special kind of fasting and spiritual practice, often observed for three consecutive days. "Pachkan" (also spelled as "Pachkhan") is the formal statement of intention or vow taken before commencing any religious practice such as fasting, including Upvaas (fast).

Trivihar Upvaas usually involves three days of consecutive Upvaas (complete fasting from food and sometimes even water, depending on the individual's ability and the sect's tradition). "Trivihar" refers to the threefold control—of mind, speech, and body—practiced during this period, emphasizing purity in thoughts, words, and actions.

Typical Pachkan for Trivihar Upvaas

The Pachkan is recited before starting each Upvaas and sets the boundaries for the fast, such as not eating, not drinking (or only drinking boiled water during certain times), and avoiding certain places or activities.

A simplified version of a Trivihar Upvaas Pachkan in Hindi/Sanskrit is as follows (actual wording may vary by sect and tradition):

``` Micchāmi Dukkaḍaṁ. Aaj thi aagli __________ (tarikh) sudhi, huṁ trivihar upvaas no pachkhan bandhu chuṁ. Aa samay doraan, huṁ ann, jal, ane ras kaī pan nahi levuṁ. Huṁ apni indriyo, man, vachan, ane kaya par niyantran rakhīsh ane dharmik anusashan pālīsh. Micchāmi Dukkaḍaṁ. ```

Translation: I seek forgiveness for any transgressions. From today until _______ (date), I accept the vow (pachkan) of Trivihar Upvaas. During this time, I will not take any food, water, or other liquids. I will control my senses, mind, speech, and body, and observe religious discipline. I seek forgiveness for any transgressions.

Note:

• The exact Pachkan wording and procedure may differ based on Jain sects (Shwetambar, Digambar, Sthanakvasi, Terapanthi, etc.) and local customs.
• It is best to consult your local Jain monk, nun, or knowledgeable elder for the precise Pachkan and guidance for Trivihar Upvaas.

Purpose: Taking Pachkan before Upvaas is essential in Jainism, as it formally sets your intention and helps maintain discipline and awareness during the fast, which is considered a key part of spiritual purification (tapasya).

If you need the Pachkan in another language or more specific details, please provide your sect or tradition.