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 A126947 The sequence c[n] defined in A126940. 1
 0, 2, 4, 12, 42, 132, 414, 1320, 4198, 13322, 42308, 134392, 426832, 1355612, 4305518, 13674594, 43431194, 137939776, 438104256, 1391442706, 4419296770, 14035924512, 44578852058, 141584833642, 449681053086, 1428211232054, 4536075755738, 14406820782444 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS FORMULA Empirical g.f.: -2*x*(x^2+1) / (x^6+4*x^5+4*x^4+7*x^3+x^2+2*x-1). - Colin Barker, Apr 08 2013 CROSSREFS Sequence in context: A244035 A340025 A126942 * A188494 A202668 A200222 Adjacent sequences:  A126944 A126945 A126946 * A126948 A126949 A126950 KEYWORD nonn AUTHOR N. J. A. Sloane, Mar 18 2007 STATUS approved

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Last modified December 7 18:19 EST 2021. Contains 349585 sequences. (Running on oeis4.)