= (128) = 



abfolutus ingrederctur '-, ita vt effe debcat e>3, idcoquc 

 !-+-£>• 4., vndc hic excliiduntur cafus (n — 4,1), (>/ — 4, ;), 

 (n — 4,3)". quorum quidcin prinius ex N". II. tcrtius autcra 

 per le datur, n.cciius \cro rcucra nuuct iucoguitus. 



\ 1. Statuamus porro j — i, /> ~ « — 5, ^ — ^, ct 

 aequatio crit 



(I, « — 5) (« - =r (I, (I -4- <, « — 5), 

 vnde fit ? ~ - 



(«—5,1-1-0 = ^ 



.5, i) (n — 4,^1 



vbi ob formulam (n — ^^^) dcbet efTc <^>- 4., idcoquc i-f-<^>5, 

 vnde hinc cxcluduntur cafus (;/— 5,1), (w — 5, 2), («— 5^3)» 

 (n — 5,4-), quorum quidcm primus e\ N*. 11. conrtar, quar- 

 tus ^cro pcr fc datur , ita vt hic occurraut duo cafus ciiam- 

 iiunc inco^niti '^n — 5, 2) ct [^n — 5,3;- 



VIT. Simili modo fi vltcrius fumamus aizi, b-n — 6 

 ct f r= >! , prodibit 



(« — 6, I -f- >l) = (n-^.)(n-5,yH 



\bi rcuera occurrunr trcs fcquentes cafus: (;/ — 6, 2), (;/ — 6, 3), 

 (w — 6,4.), qui adhuc mancnf incogniti, atquc hoc modo pro- 

 grcdi liccbit, quousquc ncccffc fucrit; vndc patct numcriiiTi 

 caliium incognitorum continuo aut;cri, ita vt terminorum /' ct 

 (j al'cr futurus fit vcl 2, vcl 3, \cl 4., ctc. qui igitur cafus 

 adhuc dcfinicndi rcftaut. 



Vni. Sumamus nunc primo /Tmi, b~C^ f— i, 

 vt acquatio noltra fiat 



(1,0 (i-l-^x) — (^ (=,0> 



vnde 



