Opdscum 4*5 



25 »n' 4- 5 w 



2 



omnes numeros triangulares compraehendant, si unaquaetfue 

 earum ponatur 



to'4-(2 A-+-1 )TO-f.A'4-A 

 = ^2 



4m''-4-(4A-f-2)m4-A'-+-A 

 4- 2 



_, 4 m' 4- ( 4 g 4- 3 ) TO -f-g' + g 



16to'4-(8/4-4)to4-/»4-/ 



melhodo superior! adhibita, inveniemus 



25 to'4- 5 TO _to''4- to 4 m' 4- 2 to 4 m'— 2 to 16to'4-4to 



2 ~ 2 "*" 2 "^ 2 "*" 2 



25 to'4-15 to4-2 m'— to 4to'4-2to 4to'4-2to 16to'4-12to4-2 



2 ~ 2 "^ 2 "' 2 "^ ~2 



25 to''4- 25 to4- 6 to'4-to 4to'4-2to 4to'4-2to 16to'+20to4-6 



2 — 2 "^ 2~ "^ 2 "^ 2 



25TO'4-35ra4-12 m''4-3TO4-2 4to'4-6to4-2 4to'4-6to4-2 1twi''4-20TO 4-6 



2 ~ 2 "* 2 ^ 2 "^ 2 



25to'4-45to4-20 m''-\-rn 4m'4-6TO4-2 4to''4-10to4-6 16m'4-28m4-12 



2 — ~1~'^ 2 ' 2 "^ ^2 



ex quibus formulis colliglmus, iinanjquamque formularum 



25 m'4- 5 TO 25 m'4- 1 5 to-^- 2 25 m''4-25 m4-6 25 to'-|-35 to -4- 1 2 



2 ' 2 ' 2 ♦ 2 ' 



25 to'4- ^5 m -1-20 . . 



■ , ideoque quemcumque numerutn tnangularem 



T. n. 54 



