Further to my comment of 26 November 2013, I now consider that it is possible for e to be replaced by other values but only because the general formula for any variable base n should be the constant n^(u/logn). When n equals e, log n will be clearly 1. The fact that n^(t/logn) has to be a constant particularly when applied to i that is n^(ti/logn) undermines virtually all the arguments in Riemann's 1859 paper. submitted by Peter L. Griffiths.