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 A174565 Expansion of (1+3*x)/((1-x)*(1+3*x+4*x^2)). 1
 1, 1, -3, 9, -11, 1, 45, -135, 229, -143, -483, 2025, -4139, 4321, 3597, -28071, 69829, -97199, 12285, 351945, -1104971, 1907137, -1301523, -3723975, 16378021, -34238159, 37202397, 25345449, -224845931, 573156001, -820084275, 167628825, 2777450629, -9002867183 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Bisection of A107443. LINKS FORMULA a(n) = (1/2)*(1 - A087168(n+1)). PROG (MAGMA) a087168:=func< n | &+[ Binomial(n+k, 2*k)*(-2)^(n-k): k in [0..n] ] >; [ (1-a087168(n+1))/2: n in [0..35] ]; CROSSREFS Sequence in context: A121057 A025538 A070354 * A074261 A059868 A101735 Adjacent sequences:  A174562 A174563 A174564 * A174566 A174567 A174568 KEYWORD sign AUTHOR Ralf Stephan, Nov 29 2010 STATUS approved

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Last modified September 25 10:39 EDT 2021. Contains 347654 sequences. (Running on oeis4.)