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%I #25 Mar 04 2023 04:27:10
%S 2,3,5,7,3,5,9,3,7,5,7,5,9,11,7,13,11,13,11,15,9,15,3,9,9,5,7,11,5,9,
%T 7,11,9,11,13,15,13,3,7,5,11,5,7,9,13,7,11,15,11,13,17,15,17,11,9,7,
%U 13,7,13,9,11,13,11,15,17,13,11,9,11,13,9,15,15,13,11
%N Base 9 sum of digits of prime(n).
%C a(n) is the rank of prime(n) in the base-9 dominance order on the natural numbers.
%H Vincenzo Librandi, <a href="/A239695/b239695.txt">Table of n, a(n) for n = 1..10000</a>
%H 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 a(n) = A053830(A000040(n)).
%e The fifth prime is 11, 11 in base 9 is (1,2) so a(5)=1+2=3.
%t Table[Plus @@ IntegerDigits[Prime[n], 9], {n, 1, 100}] (* _Vincenzo Librandi_, Mar 25 2014 *)
%o (Sage) [sum(i.digits(base=9)) for i in primes_first_n(200)]
%o (Magma) [&+Intseq(NthPrime(n),9): n in [1..100]]; // _Vincenzo Librandi_, Mar 25 2014
%o (PARI) a(n) = sumdigits(prime(n), 9); \\ _Michel Marcus_, Mar 04 2023
%Y Cf. A007605, A014499, A053830, A239690, A239691, A239692, A239693, A239694.
%K nonn,base
%O 1,1
%A _Tom Edgar_, Mar 24 2014
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