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 A084861 Expansion of (1-3x+4x^2-3x^3+x^4)/(1-2x)^2. 1
 1, 1, 4, 9, 21, 48, 108, 240, 528, 1152, 2496, 5376, 11520, 24576, 52224, 110592, 233472, 491520, 1032192, 2162688, 4521984, 9437184, 19660800, 40894464, 84934656, 176160768, 364904448, 754974720, 1560281088, 3221225472 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Partial sums give A084860. Binomial transform of signed version of A008795. LINKS Index entries for linear recurrences with constant coefficients, signature (4,-4). FORMULA a(n) = 3(n+3)2^(n-4), n>2. CROSSREFS Sequence in context: A117880 A027973 A103040 * A122498 A132750 A297296 Adjacent sequences:  A084858 A084859 A084860 * A084862 A084863 A084864 KEYWORD easy,nonn AUTHOR Paul Barry, Jun 12 2003 STATUS approved

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Last modified December 16 08:42 EST 2018. Contains 318158 sequences. (Running on oeis4.)