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 A113727 A Pell convolution. 0
 1, 0, 4, 4, 17, 32, 88, 200, 497, 1184, 2876, 6924, 16737, 40384, 97520, 235408, 568353, 1372096, 3312564, 7997204, 19306993, 46611168, 112529352, 271669848, 655869073, 1583407968, 3822685036, 9228778012, 22280241089, 53789260160 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Convolution of A000129(n+1) and (n+1)*(-1)^n. LINKS Index entries for linear recurrences with constant coefficients, signature (0,4,4,1). FORMULA G.f.: 1/((1-2x-x^2)(1+2x+x^2)); a(n)=4a(n-2)+4a(n-3)+a(n-4); a(n)=sum{k=0..floor(n/2), C(n-k, k)2^(n-2k)*(1+(-1)^(n-k))/2}. a(n) = A000129(n+1)/2 +(n+1)*(-1)^n/2. - R. J. Mathar, Sep 20 2012 MATHEMATICA LinearRecurrence[{0, 4, 4, 1}, {1, 0, 4, 4}, 30] (* Harvey P. Dale, May 24 2014 *) CROSSREFS Cf. A094686, A113726. Sequence in context: A294245 A117785 A117787 * A214141 A193961 A205110 Adjacent sequences:  A113724 A113725 A113726 * A113728 A113729 A113730 KEYWORD easy,nonn AUTHOR Paul Barry, Nov 08 2005 STATUS approved

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Last modified August 13 22:57 EDT 2020. Contains 336473 sequences. (Running on oeis4.)