4^6 Opuscula 



dccomponi posse in quatuor mimeros triangulares, lege ac rao- 

 do diverso ab illo, quem super exposuimus. 



Pariter teriio raodo decomponere possumus numeros trian- 

 gulares in quatuor triangulares . Etenim si numerorum trian- 

 gularium series in sex, quae sequunlur^ dividatur, 



0, 21 , 78 , 171 , etc. 



1 , 28, 91 , 190, etc. 



3, 36, 105 , 210, etc. 



6, 45, 120, 231 , etc. 

 10, 55 , 136 , 25 J, etc. 



15, 66, 153, 276, etc., 

 cum ipsarum termini generales sint, 



36 m'^- 6 w ) -j« *in 



2 

 posita unaquaque harum formularum 



-_2 _ m'~{' ( 2 /i + 1 ) m -4- A'-4- h 



_ _ 



m^ 4- ( 2 /f 4- 1 ) m -H A= -t- 1 





2 



2 

 25m*4- (10 / -H 5 ) m + /'4. / 



uiOTsIfignniir mvvxtaaa 9nprniwoif>r>p aoposbi , - ■■ ■'■ ^ 

 ^6 •" '>t 



