1. Yes, as you say it doesn't matter 2. Order of summation doesn't matter when all numbers are positive > Since A only contains positive integers doesn't sum o

1. Yes, as you say it doesn't matter 2. Order of summation doesn't matter when all numbers are positive > Since A only contains positive integers doesn't sum of 1/n for all n in A always tend towards infinity? no, think for instance sum(1/n^2) EDIT: or sum(1/2^n) which solves Zeno's paradox (Achilles vs Tortoise)