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 A097064 Expansion of (1-4x+6x^2)/(1-2x)^2. 6
 1, 0, 2, 8, 24, 64, 160, 384, 896, 2048, 4608, 10240, 22528, 49152, 106496, 229376, 491520, 1048576, 2228224, 4718592, 9961472, 20971520, 44040192, 92274688, 192937984, 402653184, 838860800, 1744830464, 3623878656, 7516192768, 15569256448, 32212254720, 66571993088 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Binomial transform of A097062. LINKS Index entries for linear recurrences with constant coefficients, signature (4,-4). FORMULA a(n) = (n-1)*2^(n-1) + 3*0^n/2. a(n) = 4*a(n-1) - 4*a(n-2), n>2. a(n) = Sum_{k=0..n} binomial(n, k)*((2k-1)/2 + 3*(-1)^k/2). a(n+1)/2 = A001787(n). From Amiram Eldar, Oct 01 2022: (Start) Sum_{n>=2} 1/a(n) = log(2) (A002162). Sum_{n>=2} (-1)^n/a(n) = log(3/2) (A016578). (End) MATHEMATICA CoefficientList[Series[(1-4x+6x^2)/(1-2x)^2, {x, 0, 30}], x] (* or *) Join[{1}, LinearRecurrence[{4, -4}, {0, 2}, 30]] (* Harvey P. Dale, May 26 2011 *) CROSSREFS Essentially the same as A036289. Cf. A001787, A002162, A016578. Sequence in context: A292218 A134401 A036289 * A352206 A294458 A333186 Adjacent sequences: A097061 A097062 A097063 * A097065 A097066 A097067 KEYWORD easy,nonn AUTHOR Paul Barry, Jul 22 2004 STATUS approved

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Last modified December 9 18:21 EST 2022. Contains 358703 sequences. (Running on oeis4.)