❖ Summary of the Question:
Regarding the well-known Takbīr recited during ʿĪd and Ayyām al-Tashrīq:
"Allāhu Akbar, Allāhu Akbar, Lā ilāha illallāh, wa-Allāhu Akbar, Allāhu Akbar, wa li-llāhi al-ḥamd"
Questions were raised:
◈ Are these exact words authentically reported from the Prophet ﷺ?
◈ Are they attributed to any Companion?
◈ Are they transmitted from any Tābiʿī?
◈ Have the ḥadīth scholars authenticated them?
❖ Answer:
الحمد لله، والصلاة والسلام علىٰ رسول الله، أما بعد!
➊ From the Prophet ﷺ:
A narration reports that the Prophet ﷺ recited the following Takbīr during ʿĪd:
"Allāhu Akbar, Allāhu Akbar, Lā ilāha illallāh, wa-Allāhu Akbar, Allāhu Akbar, wa li-llāhi al-ḥamd"
(Source: Sunan al-Dāraqutnī, 2/49, Ḥadīth: 1721)
**However, this narration is fabricated (mawḍūʿ) due to the following unreliable narrators:
◈ ʿAmr ibn Shimr – a liar (kadhdhāb)
◈ Jābir al-Juʿfī – extremely weak and a Rāfiḍī
◈ Nāʾil ibn Najīḥ – weak

➋ From the Companions:
◈ ʿAbdullāh ibn ʿAbbās (رضي الله عنه):
"Allāhu Akbar kabīrā, Allāhu Akbar kabīrā, Allāhu Akbar wa ajall, Allāhu Akbar wa li-llāhi al-ḥamd"
(Source: Muṣannaf Ibn Abī Shaybah, 2/167, Ḥadīth: 5650)

◈ Salmān al-Fārsī (رضي الله عنه):
"Allāhu Akbar, Allāhu Akbar, Allāhu Akbar"
(Source: Muṣannaf ʿAbd al-Razzāq, 11/294–295, Ḥadīth: 20581; al-Bayhaqī, 3/316)

➌ From the Tābiʿīn:
◈ Imām Ibrāhīm al-Nakhaʿī (رحمه الله):
"They would recite Takbīr on the Day of ʿArafah, each one facing the qiblah after prayer, saying:
“Allāhu Akbar, Allāhu Akbar, Lā ilāha illallāh, wa-Allāhu Akbar, Allāhu Akbar, wa li-llāhi al-ḥamd”
(Source: Muṣannaf Ibn Abī Shaybah, Vol. 2, Pg. 167, Ḥadīth: 5649)

➍ Opinions of Ḥadīth Scholars:
Even though there is no authentic sanad from the Prophet ﷺ for the famous wording, it is abundantly established from:
✔ The Companions (like Ibn ʿAbbās, Salmān al-Fārsī)
✔ The Tābiʿīn (like Ibrāhīm al-Nakhaʿī)
Hence, reciting this Takbīr is in accordance with the practice of the Salaf, and therefore valid and meritorious.
➎ Conclusion:
The commonly recited Takbīr:
"Allāhu Akbar, Allāhu Akbar, Lā ilāha illallāh, wa-Allāhu Akbar, Allāhu Akbar, wa li-llāhi al-ḥamd"
is not authentically attributed to the Prophet ﷺ, but is authentically established from the Companions and Tābiʿīn.
✔ Therefore, reciting these words during the days of ʿĪd and Ayyām al-Tashrīq is a valid and rewarding practice.

ھذا ما عندي واللہ أعلم بالصواب