The limit of a series of rationals can be irrational. (Pi^2)/6 is an accumulation point in Q. It element of the epsilon neighborhood of the partial sums Sn for a lage n. Sn is still part of Q for all n.

## (pi^2)/6

The limit of a series of rationals can be irrational. (Pi^2)/6 is an accumulation point in Q. It element of the epsilon neighborhood of the partial sums Sn for a lage n. Sn is still part of Q for all n.