Let c(n)(A) denote the codimensions of a P.I. algebra A, and assume c(
n)(A) has a polynomial growth: c(n)(A)similar or equal to/n-->infinity
qn(k). Then, necessarily, q is an element of Q [D3]. If 1 is an eleme
nt of A, we show that 1/K! less than or equal to q less than or equal
to 1/2! - 1/3! + - ... + (-1)(k)/k! approximate to 1/e, where e = 2.71
.... In the non-unitary case, for any 0 < q is an element of Q, we con
struct A, with a suitable k, such that c(n)(A)similar or equal to/n-->
infinity qn(k).