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%I #7 Jul 03 2023 11:16:20
%S 5,11,21,33,53,77,117,165,245,341,501,693,1013,1397,2037,2805,4085,
%T 5621,8181,11253,16373,22517,32757,45045,65525,90101,131061,180213,
%U 262133,360437,524277,720885,1048565,1441781,2097141,2883573,4194293,5767157
%N Partial sums of A164095.
%H Vincenzo Librandi, <a href="/A164096/b164096.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (1, 2, -2).
%F a(n) = 2*a(n-2)+11 for n > 2; a(1) = 5, a(2) = 11.
%F a(n) = (27-5*(-1)^n)*2^(1/4*(2*n-1+(-1)^n))/2-11.
%F G.f.: x*(5+6*x)/(1-x-2*x^2+2*x^3).
%o (Magma) T:=[ n le 2 select n+4 else 2*Self(n-2): n in [1..38] ]; [ n eq 1 select T[1] else Self(n-1)+T[n]: n in [1..#T]];
%Y Cf. A164095.
%K nonn
%O 1,1
%A _Klaus Brockhaus_, Aug 10 2009
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