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Sum of primes <= 3^n.
1

%I #22 Jul 02 2024 08:19:39

%S 0,5,17,100,791,5830,42468,327198,2575838,20476640,166554645,

%T 1353822880,11150031169,92258920888,769310640408,6447635236133,

%U 54292816788848,459112338326268,3896226837717653,33172345145637461,283258796052356059,2425130743589880412,20812174068479995267

%N Sum of primes <= 3^n.

%C For large n, these numbers can be closely approximated by the number of primes < (3^n)^2. For example, the sum of primes < 3^12 = 11150031169. The number of primes < (3^12)^2 = 3^24 = 11152818693. The error here 0.000250.

%C The second term, 5, is the addition of the primes 2 and 3 since we defined the sequence as less than or equal.

%H Amiram Eldar, <a href="/A139390/b139390.txt">Table of n, a(n) for n = 0..43</a> (calculated using Kim Walisch's primesum program)

%H Cino Hilliard, <a href="http://docs.google.com/Doc?id=dgpq9w4b_26dtrq634m">Sum of Primes</a>. [broken link]

%H Cino Hilliard, <a href="http://docs.google.com/Docdocid=dgpq9w4b_11m7tc9r&amp;hl=en">Sumprimesgmp program</a>. [broken link]

%H Kim Walisch, <a href="https://github.com/kimwalisch/primesum">Sum of the primes below x (primesum)</a>.

%F a(n) = A034387(A000244(n)). - _Amiram Eldar_, Jul 02 2024

%o (PARI) a(n) = vecsum(primes([1, 3^n])); \\ _Michel Marcus_, Jul 02 2024

%Y Cf. A000244, A034387, A130739.

%K nonn

%O 0,2

%A _Cino Hilliard_, Jun 09 2008

%E Duplicated term removed and a(20)-a(22) added by _Amiram Eldar_, Jul 02 2024