Sum of primes dividing the repunit numbers with a prime number of digits [A031974] (with repetition).
A064768
Sum of primes dividing the repunit numbers with a prime number of digits [A031974] (with repetition).
Terms
- a(0) =11a(1) =40a(2) =312a(3) =4888a(4) =534888a(5) =265371785a(6) =5365294080a(9) =77843964391
External references
- oeis: A064768