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A323085
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Semiprimes that are the sum of the first k terms of A092190 for some k.
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1
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4, 14, 8567, 16499, 151211, 344891, 418831, 585197, 1049882, 1186582, 1671029, 2503966, 2989387, 4802311, 8291795, 9769711, 11420129, 13279957, 13677063, 15356513, 16258813, 24318863, 26874293, 39317497, 42862751
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OFFSET
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1,1
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COMMENTS
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If we call the semiprime numbers A001358 level 1, and A092190 level 2, then this sequence is level 3.
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LINKS
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EXAMPLE
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a(2) = 14 = Sum_{i=1..2} A092190(i).
a(3) = 8567 = Sum_{i=1..13} A092190(i).
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MATHEMATICA
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f[w_] := Select[Most@ NestWhile[Append[#1, {#2, #2 + #1[[-1, -1]]}] & @@ {#, w[[Length@ # + 1]]} &, {{#, #}} &@ First[w], #[[-1, -1]] <= Max@ w &][[All, -1]], PrimeOmega@ # == 2 &]; Block[{s = Select[Range[10^6], PrimeOmega@ # == 2 &], t}, f@ f@ s] (* Michael De Vlieger, Jan 04 2019 *)
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PROG
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(C++) typedef unsigned long long int ulli;
void Level3(){ vector<ulli>::iterator low; ulli acum = 0;
for(int i = 0; i < level2.size(); i++){
acum += level2[i];
low=lower_bound (semiprimes.begin(), semiprimes.end(), acum);
if(semiprimes[low - semiprimes.begin()] == acum){
printf("%llu\n", acum);
} } } //where level2 is a vector with A092190.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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