-3»^ ) 7+ ( ^??- 

 Hinc concluditur 



f * 4i ■ llt I< 



III _ >»♦ 1 5« I X 



Quamobrem cuidum ell tocam fummam forc x Hr f ~ o. 



§. 30. Confideremns nunc ctiam radices quadra* 

 tas, (iue fit a' — i, hincquc orictur ifta fcrics ; 



— i\ a — 2^ 4- 5\ cc 4- 7^ a — 12^— 1 5^ a 4- 22* 

 -f 26^— etc. =: o^ 



▼nde C\ terminos vniratem et a confinentcs a (c inniccm 

 icparcmus, binas obtincbimus fencs nihilo aequalcs, rcihcet: 



— 2^— i^^^^- 22^ + 26^— 40^ — 70'' -f 92^-f ctc. — o 

 ct 



— i\ a -f- 5\ a + 7\ a— i^''. a— 35'^. a -V- 51*- a 



-h 57^. a — etc. ~ o. 



Quod fi vero harum ferierum vcritatcm codcm modo, quo 

 ante fiimu<i vfi, oftenderc vellcmus, vnamquamquc in qua- 

 tuor alias fcrics difccrpi oporicrct, Tt fi;ilicet tandcm ad 

 diffcrcntias conllantcs pcrucniremns. At vcro fi quis 

 haiic operam rufcipcrc volucrir, ctrtus cfic potcrit , ag- 

 grcgatum omQium (ummarum partialiuin torc ^ o. 



$. 31. Nunc gencnilifiime totnm ncj>otium com- 

 pIccTamur, fitquc a" ~ 1 , ct quacr.nniu*' firicm , qu.ic con- 

 tincar tantum potcflrifcs cC. Hnnc in fincm ex omnibtis 

 no('ris nuincris pciuaeond bus exccrp.imus cos , qui pcr n 

 diihfi rclinquiint idcm rtfiduam r. .Sint if,ifur illi numc- 

 ri pcntagonalcs A, B, C, H, K , ctc omncs fijilicct fi)r- 



mac 



