1/13*{1-1/5*[1-1/7*(1-1/11)]}/451/493*377/943/429/391-38/455

1/13*{1-1/5*[1-1/7*(1-1/11)]}/(451/493*377/943/429/391-38/455)
=1/13*{1-1/5*[1-1/7*10/11]}/(493/451*377/943*429/391-38/455)
=1/13*{1-1/5*[1-10/77]}/[(11*41)/(17*19)*(13*29)/(23*41)*(17/23)/(11*39)-38/455]
=1/13*{1-1/5*67/77}*(17*29)/(1/3-38/455)
=1/13*{1-67/385}*1365/341
=1/13*4/5*1365/341
=4*21/341
=84/341

1/13*{1-1/5*[1-1/7*(1-1/11)]}/(451/493*377/943/429/391-38/455)
=1/13*{1-1/5*[1-1/7*10/11]}/(493/451*377/943*429/391-38/455)
=1/13*{1-1/5*[1-10/77]}/[(11*41)/(17*19)*(13*29)/(23*41)*(17/23)/(11...