[ggrothendieck]

David P. Ellerman has a mathematical approach to accounting based on what he refers to as the Pacioli group. A provisional element of the Pacioli group looks like x//y where x and y are non-negative integers and we form equivalence classes based on x//y and u//v being equivalent if the cross sums x+v and y+u are equal. The group operation is x//y + u//v = (x+u)//(y+v) and the inverse of x//y is y//x . The identity element is 0//0. For more info see, for example, https://ellerman.org/wp-content/uploads/2012/12/DEB-Math-Mag...