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 A211388 Expansion of 1/((1-2*x)^6*(1-x)). 3
 1, 13, 97, 545, 2561, 10625, 40193, 141569, 471041, 1496065, 4571137, 13516801, 38862849, 109051905, 299565057, 807600129, 2141192193, 5592842241, 14413725697, 36698062849, 92408905729, 230359564289, 568965726209, 1393398120449 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..1000 M. H. Albert, M. D. Atkinson, R. Brignall, The enumeration of three pattern classes using monotone grid classes, El. J. Combinat. 19 (3) (2012) P20. Section 5.5.1 Harry Crane, Left-right arrangements, set partitions, and pattern avoidance, Australasian Journal of Combinatorics, 61(1) (2015), 57-72. Index entries for linear recurrences with constant coefficients, signature (13,-72,220,-400,432,-256,64). FORMULA a(n) = 1 + 2^(n-2)*n*(n^4 + 10*n^3 + 55*n^2 + 110*n + 184)/15. - Bruno Berselli, Feb 08 2013 A211386(n) = a(n) - 2*a(n-1). - R. J. Mathar, Feb 08 2013 MATHEMATICA CoefficientList[Series[1 / ((1 - 2 x)^6 (1 - x)), {x, 0, 30}], x] (* Vincenzo Librandi, Sep 10 2013 *) PROG (MAGMA) m:=24; R:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-2*x)^6*(1-x)))); // Bruno Berselli, Feb 08 2013 CROSSREFS Cf. A054849 (first differences). Sequence in context: A141894 A275879 A160554 * A125350 A049294 A198480 Adjacent sequences:  A211385 A211386 A211387 * A211389 A211390 A211391 KEYWORD nonn,easy AUTHOR R. J. Mathar, Feb 07 2013 STATUS approved

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Last modified December 13 23:14 EST 2019. Contains 329974 sequences. (Running on oeis4.)