Auf bin Malik bin Nadlah عوف بن مالك بن نضلة - أبو الأحوص · The Book on Jana''iz (Funerals)

"Zaid bin Arqam would say four Takbir for our funerals. (Once) he said five Takbir for a funeral so we asked him about that and he said: 'The Messenger of Allah would say those Takbir.'"