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 A115719 Products of two primes that are not Chen primes. 0
 1849, 2623, 3139, 3397, 3721, 4171, 4429, 4453, 4819, 5329, 5767, 5917, 6241, 6283, 6493, 7009, 7081, 7439, 7519, 7663, 8137, 8299, 9211, 9409, 9589, 9847, 9943, 9991, 10363, 10553, 10609, 11023, 11653, 11773, 11899, 11911, 11929, 12169, 12629, 12877 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Subset of semiprimes A001358 such that neither prime factor is a Chen prime. See also A109611 (Chen primes: primes p such that p + 2 is either a prime or a semiprime), A102540 (primes that are not Chen primes). LINKS Table of n, a(n) for n=1..40. FORMULA {p*q such that p is in A102540 and q is in A102540}. {s such that s is in A001358 AND p|s IMPLIES NOT(p is in A109611}. EXAMPLE a(1) = 1849 = A102540(1)*A102540(1) = 43*43. a(2) = 2623 = A102540(1)*A102540(2) = 43*61. a(36) = 14701 = A102540(2)*A102540(13) = 61 * 241. CROSSREFS Cf. A000040, A001358, A109611, A102540. Sequence in context: A236030 A237892 A326318 * A062670 A206468 A031764 Adjacent sequences: A115716 A115717 A115718 * A115720 A115721 A115722 KEYWORD easy,nonn AUTHOR Jonathan Vos Post, Mar 09 2006 STATUS approved

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Last modified December 4 06:57 EST 2023. Contains 367557 sequences. (Running on oeis4.)