[ 43 ] 

 the gen. term of the fine of n a — 



n. n — u -f- I. n—u +2 - - to ~ terms 



« 



I. 2. ■? - - - - _ 



a s, a^ "^ when — is even and — when odd. 



Let « be of the form 4/ + 3. 



The cofme of 4/' + 3 X Qj—^ = c/ of 3 Q;— 4/ + 3 a = (becaufe 

 adding or fubtrading \ the circumference changes the lign of 



the cofinc) = — cs oi Qr-^p + 3 <a = — j. of 4/ T3 a. 



.'. When « is of the form 4/ + 3 the general term of the fine of 



u 



». ft — u + I. « — « + 2 - to — terms n—u—i "~" 

 , r 2 J «" 



I. 2. 3. - - — 



_ when — is even and + when odd. Whence the truth of 

 2 



the theorem will cafily appear. 



V. Cor. If the feries be arranged in a contrary order. 



2 2 

 n. n — r 3 



The fincof « A = «/ — •— — 1+ &c. when nu any odd 



I. 2. 3 ' 



F a number 



