[Advaita-l] Sanyasins

[vijay kartik]

    Dear Members,

Please forgive me if this is a very naive or utterly ignorant question.
I know that as per traditional Vedic living, a man goes through the 4 stages from Brahmacharya to Gruhastha to Vanaprastha to Sanyasin.
Of course Adi Sankara became a Sanyasin right from Brahmacharya stage as we know from his life story.
Similar to Adi Sankara, were there many Sanyasins before his time like him who did not pass through Gruhasthasrama and Vanaprastha?
In other words, even before Adi Sankara, did a long list of Sanyasins exist similar to him? 
Please clarify

Vijay