1 36 REV. T. P. KIRKMAN ON THE 



If a:=5c-j-c, c-yo, we have, reasoning as before, 



(6Pc) = [4Pc-i], whence 



20- 



^=~r2^-2oO-^^^'+^^^'+^®^-^0 



=--2o1t2C®'*^^-^+^®'*^''-^+^^'*^^-^+^^**^'^-^); 



whence 



-56.*5c_3-32.%_4|. 



Let now (sPx)', the sum of the e-f I terms, 

 _/22(9i=i:*2,.2+9.^=:6:*2^-7+,&c.H-9(c-l).*2c-2)^(G) 

 be supposed to be 



(,P,)'=A^2+Ba:+(CV+D:r+E)*2^_i+F, 



— (sP.-s) =— A:r2+(10A— B):r— (Ca;2_10C:^:+25C 



4-D:r— 5D 



20-122, 



