Summing the Reciprocals of Primes (opens in new tab)

The sum of the reciprocals of the primes diverges, but very slowly. The sum of the reciprocals of the first 100 primes is 2.106… The sum of the reciprocals of the first 1,000 primes is 2.457… For the first 10,000 it’s 2.709… And it keeps creeping up, ever more slowly. To get the sum to […]