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 A075593 a(1) = 1, a(2n) = prime, a(2n+1) = composite and sum of two successive terms is alternately composite or prime. 6
 1, 3, 4, 2, 9, 5, 6, 19, 10, 11, 8, 7, 12, 13, 16, 17, 14, 31, 22, 23, 18, 37, 24, 41, 20, 29, 30, 47, 26, 43, 28, 53, 36, 59, 38, 61, 40, 71, 32, 67, 34, 83, 44, 73, 54, 79, 48, 97, 42, 101, 50, 103, 46, 89, 60, 109, 58, 107, 56, 113, 66, 137, 62, 127, 52, 131, 68, 139, 72 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS This is not a permutation of the positive integers; odd composites > 9 will not appear in the sequence. - Klaus Brockhaus, Feb 06 2006 LINKS CROSSREFS Cf. A075594, A103824, A103825. Sequence in context: A199271 A215175 A091477 * A145421 A338245 A286681 Adjacent sequences:  A075590 A075591 A075592 * A075594 A075595 A075596 KEYWORD nonn AUTHOR Amarnath Murthy, Sep 27 2002 EXTENSIONS Extended by Ray Chandler Feb 16 2005 STATUS approved

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Last modified May 6 23:37 EDT 2021. Contains 343600 sequences. (Running on oeis4.)