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 A208136 Subsequence of A208135 with numbers that match duplicate factors deleted. 2
 9, 33, 35, 39, 49, 57, 65, 129, 133, 135, 147, 159, 161, 183, 201, 215, 225, 235, 237, 249, 259, 267, 287, 291, 303, 371, 385, 393, 413, 417, 423, 427, 459, 489, 497, 519, 525, 527, 537, 543, 573, 579, 591, 605, 609, 615, 633, 651 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The polynomials having coefficients in {0,1} are enumerated at A206073.  They include the following: p(1,x) = 1 p(2,x) = x p(3,x) = x + 1 p(9,x) = x^3 + 1 = (x + 1)(x^2 - x + 1) p(18,x) = x(x + 1)(x^2 - x + 1) p(33,x) = (x + 1)(x^4 - x^3 + x^2 - x + 1). A208135 gives those n for which p(n,x) has a factor containing a negative coefficient; A208136 is a subsequence of A208135 in which, for each p(n,x), there is a factor containing a negative coefficient, and that factor has not already occurred for some p(k,x) with k= n, ans = Delete[ans, Map[Take[{#[[1]]}] &,     Rest[Position[ans, Flatten[ans[[n]][[2]]]]]]]; n++]; Map[#[[1]] &, ans] (* Peter J. C. Moses, Feb 22 1012 *) CROSSREFS Cf. A208135, A206073, A206284. Sequence in context: A061913 A264512 A231764 * A130444 A177697 A287534 Adjacent sequences:  A208133 A208134 A208135 * A208137 A208138 A208139 KEYWORD nonn AUTHOR Clark Kimberling, Feb 23 2012 STATUS approved

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Last modified August 14 03:05 EDT 2020. Contains 336477 sequences. (Running on oeis4.)