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 A134376 Numbers whose sum of prime factors (counted with multiplicity) is not prime. 26
 1, 4, 8, 9, 14, 15, 16, 18, 20, 21, 24, 25, 26, 27, 30, 32, 33, 35, 36, 38, 39, 42, 44, 46, 49, 50, 51, 55, 57, 60, 62, 64, 65, 66, 68, 69, 70, 72, 74, 77, 78, 81, 84, 85, 86, 87, 91, 92, 93, 94, 95, 98, 100, 102, 105, 106, 110, 111, 112, 114, 115, 116, 119, 120, 121, 122 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The first term is 1, since 1 has no prime factors and so the sum of prime factors evaluates to zero. Conjecture: a(n) ~ n. - Charles R Greathouse IV, Apr 28 2015 LINKS Hieronymus Fischer, Table of n, a(n) for n = 1..10000 EXAMPLE a(2) = 4, since 4 = 2*2 and 2+2 = 4 is not prime. a(5) = 14, since 14 = 2*7 and 2+7 = 9 is not prime. PROG (PARI) sopfr(n)=my(f=factor(n)); sum(i=1, #f~, f[i, 1]*f[i, 2]) is(n)=!isprime(sopfr(n)) \\ Charles R Greathouse IV, Apr 28 2015 CROSSREFS Cf. A000040, A001222, A100118, A046363, A133620, A133621, A133880, A133890, A133900, A133910, A133911, A134330, A134331, A134332, A134333, A134334, A134344, A078177. Sequence in context: A010429 A140282 A161757 * A163408 A060299 A120512 Adjacent sequences:  A134373 A134374 A134375 * A134377 A134378 A134379 KEYWORD nonn AUTHOR Hieronymus Fischer, Oct 23 2007 EXTENSIONS Edited by the author at the suggestion of T. D. Noe, May 20 2013 STATUS approved

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Last modified May 26 13:05 EDT 2019. Contains 323586 sequences. (Running on oeis4.)