IS6 EXERCITATIONES 



18. Ponamus nunc in genere S(«)ir:P, ct 

 lequentem lummamS (« -^- 2) — Q. erit 



^ TH-2 ~n-*-3 ^^ 3 ^"^ 2. J ** 



, (n -f- 5) (n -t- 7 ) (?t 4-8) yn+t 



ex quibus colligitur fore 



Hinc ergo ex valore S(«) definiri poteft valor 

 S (« 4- 2) excepto quidem cafu « — i , quia tum 

 in /PA£ occurret /^. 



At quia iam conftat cafus 



~fi hic pro P fumatur , fiet 



${$)=,-? X- 'if? d X- X xftA^ , 



quae per integrationem euoluta dat 



S(5)-5o(i-i5XA'-V-iox'-(n-2A:~9Ar;i;)y(i-4^)> 

 Pofito ergo a: = i fit S (5) = ^, = ^, , ideoquc 

 - — s ^ v5/ — • "" 555« 



19. Sit porro « z: 5 et 



Pzr 55(1 — 1 5 .rA'+ ioa:^- (i + 2;v— 9 Ar:i;)T^(i-43?) 

 erit S (7) 3= P^^ - 3/P ^^ - 2 ^ xf^^) , 

 quibus integralibus euolutis tandem repcritur : 



S(7) 



