In Morocco, a notary public has to keep Record Books where he/she records details of acts, deeds and ALL transactions INSTANTLY. Every Record Book should have a serial number, 01, 02 etc.... Every entry in the Record Book bears a number as well i.e, O1, 02 etc... but a Record Book cannot, by law, exceed 200 pages. Record Books have specifications that are clearly and precisely defined by the relevant regulations.
Traditionally, the Record Book used to be called كناش الجيب; it is called مذكرة الحفظ today.
In the document you are translating, 23 refers to the serial number of the Record Book, 55 to the serial number of the act/transaction while 146 refers to the page number.

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Note added at 8 hrs (2021-04-02 08:13:57 GMT)
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It is a massive book where the notary public records/writes down every single detail of every notarial act INSTANTLY. It has specific specifications in terms of size and strict regulations related to use. Documents provided by clients are mentioned and referenced in the Record Book but are kept separately and safely in the notary public's office as he/she carries around the Record Book wherever they go for work.