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A139390
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Sum of primes <= 3^n.
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1
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0, 5, 17, 100, 791, 5830, 42468, 327198, 2575838, 20476640, 166554645, 1353822880, 11150031169, 92258920888, 769310640408, 6447635236133, 54292816788848, 459112338326268, 3896226837717653, 33172345145637461, 283258796052356059, 2425130743589880412, 20812174068479995267
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OFFSET
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0,2
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COMMENTS
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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.
The second term, 5, is the addition of the primes 2 and 3 since we defined the sequence as less than or equal.
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LINKS
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FORMULA
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PROG
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(PARI) a(n) = vecsum(primes([1, 3^n])); \\ Michel Marcus, Jul 02 2024
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CROSSREFS
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KEYWORD
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nonn,changed
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AUTHOR
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EXTENSIONS
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Duplicated term removed and a(20)-a(22) added by Amiram Eldar, Jul 02 2024
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STATUS
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approved
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