Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates: The Prophet (peace and blessings be upon him) used to say twelve takbirs in the two Eid prayers: seven takbirs in the first rak'ah and five takbirs in the second. He would go by one route and return by another.
Al-Tabarani recorded it in al-Mu'jam al-Kabir; its chain contains a narrator, Sulayman bin Arqam, and he is da'if (weak).