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%I #10 Sep 08 2022 08:46:14
%S 1,4,9,16,25,37,52,69,88,109,133,160,189,220,253,289,328,369,412,457,
%T 505,556,609,664,721,781,844,909,976,1045,1117,1192,1269,1348,1429,
%U 1513,1600,1689,1780,1873,1969,2068,2169,2272,2377,2485,2596,2709,2824,2941,3061,3184,3309,3436,3565,3697
%N Partial sums of A072154.
%H Colin Barker, <a href="/A265078/b265078.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1,0,0,1,-2,1).
%F G.f.: (1+x)^2*(1-x+x^2)*(1+x+x^2) / ((1-x)^3*(1+x+x^2+x^3+x^4)).
%F a(n) = 2*a(n-1) - a(n-2) + a(n-5) - 2*a(n-6) + a(n-7). - _Vincenzo Librandi_, Jan 01 2016
%t LinearRecurrence[{2, -1, 0, 0, 1, -2, 1}, {1, 4, 9, 16, 25, 37, 52}, 60] (* _Vincenzo Librandi_, Jan 01 2016 *)
%o (PARI) Vec((1+x)^2*(1-x+x^2)*(1+x+x^2)/((1-x)^3*(1+x+x^2+x^3+x^4)) + O(x^70)) \\ _Colin Barker_, Jan 01 2016
%o (Magma) I:=[1,4,9,16,25,37,52]; [n le 7 select I[n] else 2*Self(n-1)-Self(n-2)+Self(n-5)-2*Self(n-6)+Self(n-7): n in [1..60]]; // _Vincenzo Librandi_, Jan 01 2016
%Y Cf. A072154.
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_, Dec 29 2015
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