seofontyne [OE]
seventene [MI]
seventeen [ME]
seventien
https://www.etymonline.com/word/seventeen#etymonline_v_34224
https://www.merriam-webster.com/dictionary/seventeen
https://quod.lib.umich.edu/m/middle-english-dictionary/dictionary/MED39689
https://bosworthtoller.com/27464