This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A064768 #7 Dec 15 2017 17:35:42 %S A064768 11,40,312,4888,534888,265371785,5365294080,1111111111111111111, %T A064768 11111111111111111111111,77843964391,57336415063797550469, %U A064768 2212394296770453025145,201763709900322803748658482662 %N A064768 Sum of primes dividing the repunit numbers with a prime number of digits [A031974] (with repetition). %Y A064768 Cf. A031974, A001414. %K A064768 nonn,base %O A064768 1,1 %A A064768 _Jason Earls_, Oct 18 2001