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A092190
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Semiprimes that are the sum of the first n semiprimes for some n.
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8
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4, 10, 58, 185, 219, 254, 377, 589, 843, 917, 1247, 1707, 2157, 2519, 2642, 2771, 3755, 4227, 5078, 5633, 6433, 6638, 7053, 9031, 15469, 16109, 17414, 18763, 19109, 21281, 22421, 23591, 26827, 28093, 35489, 35978, 36471, 37469, 38987, 41578, 42634
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OFFSET
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1,1
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LINKS
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Zak Seidov, Table of n, a(n) for n = 1..5000
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FORMULA
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Equals A062198 intersect A001358. - M. F. Hasler, Sep 23 2012
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EXAMPLE
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10 is a term because the sum of the first two semiprimes 4 and 6 is 10.
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MATHEMATICA
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s = Select[Range@ 40882, PrimeOmega@ # == 2 &]; Select[Accumulate[s[[1 ;; 164]]], PrimeOmega@ # == 2 &] (* Michael De Vlieger, Sep 21 2015 *)
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PROG
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(PARI) is_A092190(N)={bigomega(N)==2 & is_A062198(N)} \\ M. F. Hasler, Sep 23 2012
(PARI) A092190(n, list=0, b=2)={my(s=0, N=0); while(n, until(bigomega(N++)==b, ); bigomega(s+=N)==b & n-- & list & print1(s", ")); s} \\ M. F. Hasler, Sep 23 2012
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CROSSREFS
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Corresponding values of n: A092189.
Sequence in context: A348514 A254078 A104363 * A328036 A222675 A328155
Adjacent sequences: A092187 A092188 A092189 * A092191 A092192 A092193
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KEYWORD
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easy,nonn
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AUTHOR
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Zak Seidov, Feb 23 2004
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STATUS
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approved
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