Cardinal numbers (part 2)

Let's continue the cardinal numbers (I don't consider the Klövsjö dialect anymore due to the fact that the reference doesn't have any cardinal numbers in it):


     H      Å      N     J
  11  [ˈɛlːɵ(ʋ)]   [ˈœlːɔʋ]    ellufu    elluv
  12  [tʰaɽʋ]    [tʰɔɽʋ]    tołf     tołv
  13  [ˈtɾɛtːæn]  [ˈtɾetːɐn]    þrettán   trettan
  14  [ˈfɪ̯ʊʈːæn]  [ˈfɪ̯ʊʈːɐn]   fjórtán    fjórtan
  15  [ˈfɛmtæn]  [ˈfæmtɐn]   femtán   femtan
  16  [ˈsɛkstæn]  [ˈsekstɐn]  sextán    sekstan
  17  [ˈsœtːæn]  [ˈʂœtːɐn]   søytján   søttan    
     [ˈʂœtːæn]
  18  [ˈat(ː)æn]  [ˈaʈːɐn]   átján    attan
  19  [ˈnɪtːæn]   [ˈnɪtːɐn]   nítján    nittan
  20  [ˈtʃɵˑɣə]   [ˈtʃɵˑɣɵ]  tjogu    tjugu

Notes: (1) Old Norse had various words for 11. In Old Icelandic it was ellifu, in Old Swedish ellufa. I assume Old Jamtlandic (N) had ellufu, but I could be wrong. What's peculiar is that the unstressed vowel hasn't become a schwa ([ə]) but either [ɵ] or [ɔ]. Maybe one considered the word being a compound el-lufu where lufu became simplified to luv giving elluv rather than "ellev"?
   (2) In Jamtlandic it's not too uncommon to double a consonant after a long vowel, e.g. ON sýta 'to lament' has become sytte [ˈsʏ.ʏtː] 'to nurse' in Jamtlandic. That seems to have happened for the numbers 17—19. Note especially 17 where the dipthong has been lost in the process. (The Hammerdal dialect always preserves diphtongs otherwise, even the short ones, which suggests one should spell "søyttan".) Also note how an unstressed -ján has become -an. It's possible the j was dropped very early.
   (3) The number 20 has a pretty diffuse etymology. Old Icelandic had tuttugu, Old Swedish tjugu. I use the etymology found here, which assumes a u-broken form of a root teg- (tegu- → tjog-).

To be continued in Part 3.