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A140235
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Partial sum of non-semiprimes A100959.
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1
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1, 3, 6, 11, 18, 26, 37, 49, 62, 78, 95, 113, 132, 152, 175, 199, 226, 254, 283, 313, 344, 376, 412, 449, 489, 530, 572, 615, 659, 704, 751, 799, 849, 901, 954, 1008, 1064, 1123, 1183, 1244, 1307, 1371, 1437, 1504, 1572, 1642, 1713, 1785, 1858, 1933, 2009
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OFFSET
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1,2
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COMMENTS
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This is to semiprimes A001358 as A051352 is to primes A000040. Equivalently, this is to non-semiprimes A100959 as A051349 is to nonprimes A018252.
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LINKS
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Table of n, a(n) for n=1..51.
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FORMULA
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a(n) = Sum{k=1..n} A100959(k).
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EXAMPLE
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a(5) = 18 = 1 + 2 + 3 + 5 + 7.
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MATHEMATICA
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Accumulate[Select[Range[100], PrimeOmega[#]!=2&]] (* Harvey P. Dale, Aug 22 2021 *)
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CROSSREFS
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Cf. A000217, A001358, A018252, A034387, A051349, A051352, A062198, A072000, A100959, A140234.
Sequence in context: A025210 A340648 A140126 * A224214 A010000 A183199
Adjacent sequences: A140232 A140233 A140234 * A140236 A140237 A140238
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KEYWORD
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easy,nonn
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AUTHOR
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Jonathan Vos Post, May 13 2008
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EXTENSIONS
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Corrected and edited by Giovanni Resta, Jun 20 2016
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STATUS
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approved
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