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 A162917 Numbers n which are not in A161983. 5
 1, 2, 6, 7, 8, 9, 15, 16, 17, 18, 19, 20, 28, 29, 30, 31, 32, 33, 34, 35, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 120, 121, 122, 123, 124, 125, 126, 127, 128 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS They have a block structure: A000384(n) is followed by the next n integers. Numbers k with the property that the largest Dyck path of the symmetric representation of sigma(k) has a central peak. (Cf. A237593.) - Omar E. Pol, Aug 28 2018 Union of nonzero terms of A000384 and A317303. - Omar E. Pol, Aug 29 2018 LINKS FORMULA A000027 \ A161983. EXAMPLE From Omar E. Pol, Aug 28 2018: (Start) Also, written as an irregular triangle in which the row lengths are the positive even numbers, the sequence begins:    1,  2;    6,  7,  8,  9;   15, 16, 17, 18, 19, 20;   28, 29, 30, 31, 32, 33, 34, 35;   45, 46, 47, 48, 49, 50, 51, 52, 53,  54;   66, 67, 68, 69, 70, 71, 72, 73, 74,  75,  76,  77;   91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104; ... Row sums give A035328, n >= 1. Column 1 gives A000384, n >= 1. Column 2 gives A130883, n >= 1. Right border gives the positive terms of A014107, also the odd-indexed terms of A000096. (End) CROSSREFS Complement of A161983. Cf. A000096, A000384, A014107, A035328, A130883, A237593, A317303. Sequence in context: A080780 A138168 A047279 * A250183 A260139 A118471 Adjacent sequences:  A162914 A162915 A162916 * A162918 A162919 A162920 KEYWORD nonn,tabf AUTHOR Juri-Stepan Gerasimov, Jul 17 2009 EXTENSIONS 119 removed by R. J. Mathar, Jul 19 2009 STATUS approved

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Last modified April 20 23:46 EDT 2021. Contains 343143 sequences. (Running on oeis4.)