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T(n,n-2), where T is the array in A026374.
2

%I #11 Dec 31 2021 18:02:17

%S 1,4,11,17,30,39,58,70,95,110,141,159,196,217,260,284,333,360,415,445,

%T 506,539,606,642,715,754,833,875,960,1005,1096,1144,1241,1292,1395,

%U 1449,1558,1615,1730,1790,1911,1974,2101,2167,2300

%N T(n,n-2), where T is the array in A026374.

%H Reinhard Zumkeller, <a href="/A026381/b026381.txt">Table of n, a(n) for n = 2..1000</a>

%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (1,2,-2,-1,1).

%F G.f.: z^2*(1+3z+5z^2)/[(1-z)^3*(1+z)^2]. - _Emeric Deutsch_, Jan 25 2004

%t Drop[CoefficientList[Series[z^2(1+3z+5z^2)/((1-z)^3(1+z)^2),{z,0,50}],z],2] (* or *) LinearRecurrence[{1,2,-2,-1,1},{1,4,11,17,30},50] (* _Harvey P. Dale_, Dec 31 2021 *)

%o (Haskell)

%o a026381 = flip a026374 2 -- _Reinhard Zumkeller_, Feb 22 2014

%K nonn

%O 2,2

%A _Clark Kimberling_