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%I #19 Jun 28 2017 17:16:24
%S 0,1,2,9,24,50,102,210,424,837,1630,3146,6024,11453,21644,40695,76176,
%T 142035,263916,488870,903060,1663998,3059166,5612483,10277448,
%U 18787150,34287916,62485371,113715448,206683725,375211710,680399005,1232533696,2230537914
%N a(n) = n*A259968(n).
%D R. K. Guy, Letter to N. J. A. Sloane, Feb 05 1986.
%H Colin Barker, <a href="/A259969/b259969.txt">Table of n, a(n) for n = 0..1000</a>
%H R. K. Guy, <a href="/A005251/a005251.pdf">Letter to N. J. A. Sloane, Feb 1986</a>
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,6,-5,2,-1).
%F G.f.: x*(x^4-6*x^3+7*x^2-2*x+1) / (x^3-x^2+2*x-1)^2. - _Colin Barker_, Jul 12 2015
%o (PARI) concat(0, Vec(x*(x^4-6*x^3+7*x^2-2*x+1)/(x^3-x^2+2*x-1)^2 + O(x^40))) \\ _Colin Barker_, Jul 12 2015
%o (Haskell)
%o a259967 n = a259967_list !! n
%o a259967_list = 3 : 2 : 2 : 5 : zipWith3 (((+) .) . (+))
%o a259967_list (drop 2 a259967_list) (drop 3 a259967_list)
%o -- _Reinhard Zumkeller_, Jul 12 2015
%Y Cf. A259968, A259967.
%K nonn,easy
%O 0,3
%A _N. J. A. Sloane_, Jul 11 2015
%E a(28)-a(33) from _Hiroaki Yamanouchi_, Jul 12 2015