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 A048503 G.f.: (1-4*x+6*x^2-2*x^3)/((1-x)^3*(1-2*x)^2). 1
 1, 3, 8, 22, 61, 165, 430, 1080, 2627, 6223, 14428, 32874, 73849, 163977, 360602, 786604, 1704127, 3670227, 7864552, 16777470, 35651861, 75497773, 159383878, 335544672, 704643451, 1476395415, 3087008180, 6442451410 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS a(n) = T(0,n)+T(1,n-1)+...+T(n,0), array T given by A048494. LINKS Vincenzo Librandi, Table of n, a(n) for n = 0..2000 Index entries for linear recurrences with constant coefficients, signature (7,-19,25,-16,4). FORMULA a(n) = (14+7*n+n^2+(n-3)*2^(n+2))/2. - T. D. Noe, Dec 11 2006 PROG (MAGMA) [(14+7*n+n^2+(n-3)*2^(n+2))/2 : n in [0..30]]; // Vincenzo Librandi, Sep 25 2011 CROSSREFS Sequence in context: A155020 A255705 A014397 * A200752 A279378 A048579 Adjacent sequences:  A048500 A048501 A048502 * A048504 A048505 A048506 KEYWORD nonn,easy AUTHOR EXTENSIONS Better definition from Ralf Stephan, Feb 05 2004 Corrected by T. D. Noe, Dec 11 2006 STATUS approved

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