147 



A (4) A (2) _|_9_1? A ( 3 ) . 3(n— a) 3^ 3 ■ 9 • (*— ("— ») 



373 3 ?■(" — 'X* — 3 ). . 



"T~ 2 (2n-f-3)(2ri-t-iJ(2n — ij 



|. 10. Lex progressionis numerorum ACO, A^), etc. a t ,a 2 , etc. 

 Tisque ad r — 3 et ^ — 4, sequentibus declaratur formulis : 



(1) A (r ) = - 2 r -~-. 2.4 .6....(rH-l)xÇ»^r-«-lX/i-rH-2) (w- ^) 



1~3.5 /-x(2wh-3X2» -H-0 (2n— r-t-2) 



(2) A( ^_ Tg | 1- 3-5 (si-i)x(n — s+-i) (/i — J-4-2) (;i — §) 



2.4.6 a'x (2«-+-3) (2/i-t-i.)- (2n— f-t-3) 



(3) ^ = H , é£>S) l C2U'V« (*—*>> 



(1.3.5 r>" 



(2i+lUl .3.5 C* — 1)) 



2 



(4) «, = H- 



(2.4.6 s) 



unde sequitur 

 A'.'') =+2^ 2.4.6....(,-f-l)x 1.2.3 



1.3.5..../- x (/-(- 2) (/•-+- 4) .... (2/-+l)(2/-4-3) 



A^ ! — -2 





2.4.6 (r-f- l) x 2.3.4. 



1.3.5 r x (/• + À) (r -f- b) ... (2r -f- 5) 



■ [s) _ I 1-3. 5 .... C-y-hl) x 1.2.3 § 



2.4.6 j x {s-t 3) (s-t-5) .... (2s-+ i; (2A--+-3) 



A «> — - 2 S 1 ' 3 - 5 H<)« 2.3.4 (£ + 1) yd 



s+1 ~ t ~ '2.4.6 s x (j-hôJ ^4-7) .... (2ah-5) ' 



C ; '■ —^1 .3.5 ( 2/ --}-l)(2r+3)' 



(2.4.6 (,-_f_i)) 2 .^ 



(6) A^ r) — . 



1.3.5 /• x (r + 4) (/■ -+- 0; fe "*" 5 ) 



19* 



