there exists an arrangement in S in which ak follows all the a, with i < k. Such sets S surely exist; for example, any set of m arrangements whose terminal elements are 1, 2, , m, respectively, will… Expand

where ,B is an ordinal, and where at for every t <,3 is likewise an ordinal. We shall call ,B the argument of the sum (I). The summands of (I) need not be all distinct; the cardinal number of times… Expand