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 A216911 Numbers that are a prime factor of a Carmichael number divisible by 3, listed in the order in which they appear in the prime factorizations of such Carmichael numbers. 1
 3, 11, 17, 5, 47, 89, 101, 197, 29, 263, 521, 1559, 173, 3011, 71, 641, 1277, 53, 317, 4583, 617, 4019, 401, 3041, 41, 479, 3347, 131, 10427, 4643, 1301, 419, 6689, 5531, 281, 55217, 251, 2417, 4001, 491, 1601, 3137, 449, 3617, 107, 2969, 4211, 6737, 1061 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Every term, other than a(1)=3, is a prime of the form 6*k - 1. LINKS Charles R Greathouse IV, Table of n, a(n) for n = 1..3744 Eric Weisstein's World of Mathematics, Carmichael Number EXAMPLE The first few Carmichael numbers that are divisible by 3 (A258801), their prime factorizations, and the terms of this sequence are as follows: . m | A258801(m) & prime factorization | prime factors not appearing earlier --+----------------------------------+---------------------------------------- 1 | 561 = 3 * 11 * 17 | a(1) = 3, a(2) = 11, a(3) = 17; 2 | 62745 = 3 * 5 * 47 * 89 | a(4) = 5, a(5) = 47, a(6) = 89; 3 | 656601 = 3 * 11 * 101 * 197 | a(7) = 101, a(8) = 197; ... CROSSREFS Cf. A002997 (Carmichael numbers), A258801 (Carmichael numbers divisible by 3). Sequence in context: A029500 A243770 A298701 * A356074 A351051 A154497 Adjacent sequences: A216908 A216909 A216910 * A216912 A216913 A216914 KEYWORD nonn AUTHOR Marius Coman, Sep 20 2012 EXTENSIONS a(26), a(34), a(43) corrected by Charles R Greathouse IV, Sep 20 2012 STATUS approved

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Last modified September 29 23:48 EDT 2023. Contains 365781 sequences. (Running on oeis4.)