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 A075566 Rearrangement of natural numbers by choosing alternately even and odd numbers such that every partial sum a(1)+...+a(n) is composite. 1
 4, 5, 6, 1, 2, 3, 12, 7, 8, 9, 18, 11, 10, 15, 14, 13, 16, 17, 24, 19, 20, 21, 30, 23, 22, 25, 26, 27, 28, 29, 32, 31, 34, 33, 38, 35, 36, 37, 40, 39, 42, 41, 46, 43, 44, 45, 50, 47, 48, 49, 54, 51, 52, 53, 56, 55, 58, 57, 60, 59, 62, 61, 66, 63, 64, 65, 68, 67, 70, 69, 74, 71 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE The first number must be composite, so a(1) = 4; next number must be odd and a(2) = 1 or 3 would make a(1)+a(2) prime, so a(2) = 5; etc. CROSSREFS Cf. A075567. Sequence in context: A154916 A077061 A072508 * A076087 A082486 A106591 Adjacent sequences:  A075563 A075564 A075565 * A075567 A075568 A075569 KEYWORD nonn,easy AUTHOR Amarnath Murthy, Sep 25 2002 EXTENSIONS Extended by Ray Chandler, Feb 13 2005 STATUS approved

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Last modified April 25 21:06 EDT 2019. Contains 322461 sequences. (Running on oeis4.)