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 A274182 Semiprimes that are the sum of the first n odd primes for some n. 1
 15, 26, 39, 158, 326, 566, 789, 961, 1159, 1262, 1369, 1478, 1591, 1718, 1849, 2582, 3085, 3829, 4659, 5587, 7697, 8891, 10189, 13885, 14695, 16838, 17281, 18187, 19111, 20057, 22546, 24131, 25798, 26938, 27515, 28102, 35566, 36886, 38919, 41739, 43199, 50885 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The set of semiprimes in A071148. Intersection of A001358 and A071148. LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE 26 appears in the sequence because 26 = 2*13 that is semiprime. Also, 3+5+7+11 = 26. 158 appears in the sequence because 158 = 2*79 that is semiprime. Also, 3+5+7+11+13+17+19+23+29+31 = 158. MAPLE P:= select(isprime, [seq(i, i=3..10^4, 2)]): select(t -> numtheory:-bigomega(t)=2, ListTools:-PartialSums(P)); # Robert Israel, Sep 23 2019 MATHEMATICA Select[a = 0; Table[a = a + Prime[k], {k, 2, 300}], PrimeOmega[#] == 2 &] PROG (PARI) s = 0; forprime(p=3, 1e4, s + = p; if (bigomega(s)==2, print1(s, ", "))) CROSSREFS Cf. A001358, A071148, A189072, A274120. Sequence in context: A050700 A373731 A263108 * A139566 A097963 A063936 Adjacent sequences: A274179 A274180 A274181 * A274183 A274184 A274185 KEYWORD nonn AUTHOR K. D. Bajpai, Jun 12 2016 STATUS approved

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Last modified July 20 14:50 EDT 2024. Contains 374459 sequences. (Running on oeis4.)