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A239690
Base 4 sum of digits of prime(n).
7
2, 3, 2, 4, 5, 4, 2, 4, 5, 5, 7, 4, 5, 7, 8, 5, 8, 7, 4, 5, 4, 7, 5, 5, 4, 5, 7, 8, 7, 5, 10, 5, 5, 7, 5, 7, 7, 7, 8, 8, 8, 7, 11, 4, 5, 7, 7, 10, 8, 7, 8, 11, 7, 11, 2, 5, 5, 7, 4, 5, 7, 5, 7, 8, 7, 8, 7, 4, 8, 7, 5, 8, 10, 7, 10, 11, 5, 7, 5, 7, 8, 7, 11, 7
OFFSET
1,1
COMMENTS
a(n) is the rank of prime(n) in the base-4 dominance order on the natural numbers.
LINKS
Tyler Ball and Daniel Juda, Dominance over N, Rose-Hulman Undergraduate Mathematics Journal, Vol. 13, No. 2, Fall 2013.
FORMULA
a(n) = A053737(A000040(n)).
EXAMPLE
The sixth prime is 13, 13 in base 4 is (3,1) so a(6)=3+1=4.
MATHEMATICA
Table[Plus @@ IntegerDigits[Prime[n], 4], {n, 1, 100}] (* Vincenzo Librandi, Mar 25 2014 *)
PROG
(Sage) [sum(i.digits(base=4)) for i in primes_first_n(200)]
(Magma) [&+Intseq(NthPrime(n), 4): n in [1..100]]; // Vincenzo Librandi, Mar 25 2014
(Haskell)
a239690 = a053737 . a000040 -- Reinhard Zumkeller, Mar 20 2015
CROSSREFS
KEYWORD
nonn,base,hear
AUTHOR
Tom Edgar, Mar 24 2014
STATUS
approved