1.1970449

This number is neither prime nor composite.

Just showing those entries submitted by 'Post': (Click here to show all)

Analogous to Brun's constant for twin primes, this constant is the sum of the reciprocals of all pairs of Cousin primes (excluding the initial 1/3 + 1/7), i.e., (1/7 + 1/11) + (1/13 + 1/17) + (1/19 + 1/23) + (1/37 + 1/41) + (1/43 + 1/47) + (1/67 + 1/71) + ... Theoretical Physicist Marek Wolf made this approximation through 2^42, as described in the paper "Generalized Brun's constants." [Post]