Is it permissible to perform the prayer by saying "Allah wa Akbar" instead of "Allahu Akbar"?

If the letter "waw" (و) is added to the takbīrat al-iḥrām (the opening takbīr, i.e., saying "Allāhu wa-akbar" instead of "Allāhu akbar"), the prayer is not valid and must be repeated according to the majority of jurists from the Shāfiʿī and Ḥanbalī schools. This addition invalidates the takbīr because it changes the meaning. As for the Mālikīs, they hold that the addition of "waw" does not invalidate the takbīr unless it is combined with elongating the "hāʾ" in the word "Allāh" (i.e., "Allāāhu wa-akbar"). Regarding replacing the "hamza" with a "waw" (i.e., saying "Allāhu wakbar" instead of "Allāhu akbar"), some scholars, such as Ibn ʿUthaymīn, permitted it based on a less common, but valid, classical Arabic linguistic usage. One must learn the correct pronunciation of the takbīr. An error in the takbīrat al-iḥrām invalidates the prayer according to many scholars. However, errors in the takbīrāt of transition (takbīrāt al-intiqāl) do not invalidate the prayer; rather, the error is compensated for by performing the prostration of forgetfulness (sujūd as-sahw) according to the Ḥanbalīs.