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 A134335 Numbers such that the arithmetic mean of their prime factors (counted with multiplicity) is integer, but not prime. 2
 15, 35, 39, 42, 50, 51, 55, 65, 77, 78, 87, 91, 92, 95, 110, 111, 114, 115, 119, 123, 140, 141, 143, 155, 159, 161, 164, 170, 183, 185, 186, 187, 189, 201, 203, 204, 209, 215, 219, 221, 222, 225, 230, 235, 236, 242, 247, 258, 259, 264, 267, 284, 285, 287, 290 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Hieronymus Fischer, Table of n, a(n) for n = 1..10000 EXAMPLE a(1) = 15, since 15 = 3*5 and (3+5)/2 = 4 is not prime. a(5) = 50, since 50 = 2*5*5 and (2+5+5)/3 = 4 is not prime. CROSSREFS Cf. A000040, A001222, A100118, A046363, A133620, A133621. Cf. A133880, A133890, A133900, A133910, A133911, A134330, A134331, A134332, A134333, A134334. Sequence in context: A253055 A338063 A111170 * A257591 A284406 A329589 Adjacent sequences:  A134332 A134333 A134334 * A134336 A134337 A134338 KEYWORD nonn AUTHOR Hieronymus Fischer, Oct 23 2007 EXTENSIONS Definition clarified by the author, May 06 2013 STATUS approved

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Last modified January 23 17:33 EST 2022. Contains 350514 sequences. (Running on oeis4.)