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 A039994 #12 Jun 03 2024 18:09:34 %S A039994 1,1,1,1,1,2,2,1,3,2,2,3,1,2,2,3,2,1,2,2,3,2,2,1,2,2,3,3,2,4,4,5,6,4, %T A039994 2,3,4,3,4,6,5,2,3,4,5,2,3,4,3,3,4,5,3,3,4,4,3,4,3,2,5,5,4,4,4,6,3,4, %U A039994 5,2,4,4,5,5,5,3,3,5,2,1,3,3,5,3,3,3,1,4,3,3,4,4,3,2,1,4,3,3,6,3,4,3,4,3,4 %N A039994 Number of primes embedded in decimal expansion of prime(n) as substrings. %F A039994 a(n) = A039995(prime(n)). %e A039994 a(26) = 2 since prime(26) = 101 and "101" has two prime subsequences, 101 and 11. %Y A039994 Cf. A039995. %Y A039994 Different from A039996. %K A039994 nonn,base %O A039994 1,6 %A A039994 _David W. Wilson_ %E A039994 Definition and example clarified by _N. J. A. Sloane_, Jun 03 2024