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%I #17 Aug 24 2017 20:59:43
%S 1,3,5,7,15,23,31,45,59,73,93,113,133,159,185,211,243,275,307,345,383,
%T 421,465,509,553,603,653,703,759,815,871,933,995,1057,1125,1193,1261,
%U 1335,1409,1483,1563,1643,1723,1809,1895,1981,2073,2165,2257,2355,2453,2551
%N a(n) = n*(n-1) + A144437(n+2).
%C First differences are 2, 2, 2, 8, 8, 8, 14, 14, 14, 20, 20, 20,... (triplicated A016933).
%H G. C. Greubel, <a href="/A163979/b163979.txt">Table of n, a(n) for n = 0..5000</a>
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1,1,-2,1).
%F a(n) = A002378(n-1) + A144437(n+2).
%F a(n) = 2*a(n-1) - a(n-2) + a(n-3) - 2*a(n-4) + a(n-5).
%F G.f.: (1 +x -x^3 +5*x^4)/( (1 +x +x^2)*(1 -x)^3 ).
%F E.g.f.: (1/3)*((7+3*x^2)*exp(x) - 4*exp(-x/2)*cos(sqrt(3)*x/2)). - _G. C. Greubel_, Aug 24 2017
%t LinearRecurrence[{2,-1,1,-2,1},{1,3,5,7,15},60] (* or *) CoefficientList[ Series[-(1+x+5x^4-x^3)/((1+x+x^2)(x-1)^3), {x,0,60}],x] (* _Harvey P. Dale_, Apr 20 2011 *)
%o (PARI) x='x+O('x^50); Vec((1+x-x^3+5*x^4)/((1+x+x^2)*(1-x)^3)) \\ _G. C. Greubel_, Aug 24 2017
%K nonn,easy
%O 0,2
%A _Paul Curtz_, Aug 07 2009
%E Edited and extended by _R. J. Mathar_, Aug 12 2009
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