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 A239693 #23 Mar 04 2023 04:26:50
%S A239693 2,3,5,1,5,7,5,7,5,5,7,7,11,7,11,5,5,7,7,5,7,7,11,11,13,5,7,5,7,5,7,
%T A239693 11,11,13,5,7,7,7,11,11,11,13,11,13,5,7,7,13,11,13,11,11,13,11,11,11,
%U A239693 11,13,13,11,13,17,13,11,13,11,13,13,5,7,5,5,7,7
%N A239693 Base 7 sum of digits of prime(n).
%C A239693 a(n) is the rank of prime(n) in the base-7 dominance order on the natural numbers.
%H A239693 Vincenzo Librandi, <a href="/A239693/b239693.txt">Table of n, a(n) for n = 1..10000</a>
%H A239693 Tyler Ball and Daniel Juda, <a href="https://scholar.rose-hulman.edu/rhumj/vol14/iss2/2">Dominance over N</a>, Rose-Hulman Undergraduate Mathematics Journal, Vol. 13, No. 2, Fall 2013.
%F A239693 a(n) = A053828(A000040(n)).
%e A239693 The fifth prime is 11, 11 in base 7 is (1,4) so a(5)=1+4=5.
%t A239693 Table[Plus @@ IntegerDigits[Prime[n], 7], {n, 1, 100}] (* _Vincenzo Librandi_, Mar 25 2014 *)
%o A239693 (Sage) [sum(i.digits(base=7)) for i in primes_first_n(200)]
%o A239693 (Magma) [&+Intseq(NthPrime(n),7): n in [1..100]]; // _Vincenzo Librandi_, Mar 25 2014
%o A239693 (PARI) a(n) = sumdigits(prime(n), 7); \\ _Michel Marcus_, Mar 04 2023
%Y A239693 Cf. A007605, A014499, A053828, A239690, A239691, A239692.
%K A239693 nonn,base
%O A239693 1,1
%A A239693 _Tom Edgar_, Mar 24 2014