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 A239691 #23 Mar 04 2023 04:26:17
%S A239691 2,3,1,3,3,5,5,7,7,5,3,5,5,7,7,5,7,5,7,7,9,7,7,9,9,5,7,7,9,9,3,3,5,7,
%T A239691 9,3,5,7,7,9,7,5,7,9,9,11,7,11,7,9,9,11,9,3,5,7,9,7,5,5,7,9,7,7,9,9,7,
%U A239691 9,11,13,9,11,11,13,7,7,9,9,5,9,11,9,7,9
%N A239691 Base 5 sum of digits of prime(n).
%C A239691 a(n) is the rank of prime(n) in the base-5 dominance order on the natural numbers.
%H A239691 Vincenzo Librandi, <a href="/A239691/b239691.txt">Table of n, a(n) for n = 1..10000</a>
%H A239691 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 A239691 a(n) = A053824(A000040(n)).
%e A239691 The fifth prime is 11, 11 in base 5 is (2,1) so a(5)=2+1=3.
%t A239691 Table[Plus @@ IntegerDigits[Prime[n], 5], {n, 1, 100}] (* _Vincenzo Librandi_, Mar 25 2014 *)
%o A239691 (Sage) [sum(i.digits(base=5)) for i in primes_first_n(200)]
%o A239691 (Magma) [&+Intseq(NthPrime(n),5): n in [1..100]]; // _Vincenzo Librandi_, Mar 25 2014
%o A239691 (PARI) a(n) = sumdigits(prime(n), 5); \\ _Michel Marcus_, Mar 04 2023
%Y A239691 Cf. A007605, A014499, A053824, A239690.
%K A239691 nonn,base
%O A239691 1,1
%A A239691 _Tom Edgar_, Mar 24 2014