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%I #25 Feb 17 2017 14:21:23
%S 1,4,10,23,53,123,286,665,1546,3594,8355,19423,45153,104968,244021,
%T 567280,1318766,3065759,7127025,16568323,38516678,89540413,208156206,
%U 483904470,1124941411,2615171499,6079536145,14133206848,32855719753,76380281708,177562612466
%N a(n) = 3*a(n-1) - 2*a(n-2) + a(n-3).
%H G. C. Greubel, <a href="/A137531/b137531.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-2,1).
%F G.f.: (1 + x) / (1 - 3*x + 2*x^2 - x^3). - _Colin Barker_, Feb 17 2017
%t LinearRecurrence[{3, -2, 1}, {1, 4, 10}, 100] (* _G. C. Greubel_, Feb 17 2017 *)
%o (PARI) a=[1,4,10];for(i=1,99,a=concat(a,3*a[#a]-2*a[#a-1]+a[#a-2]));a \\ _Charles R Greathouse IV_, Jun 01 2011
%o (PARI) Vec((1 + x) / (1 - 3*x + 2*x^2 - x^3) + O(x^40)) \\ _Colin Barker_, Feb 17 2017
%Y Cf. A159347, A097550.
%K nonn,easy
%O 0,2
%A _Paul Curtz_, Apr 25 2008
%E More terms from _Vladimir Joseph Stephan Orlovsky_, Jan 20 2009