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T(n,n-3), array T as in A054120.
0

%I #12 Oct 19 2022 08:10:06

%S 1,9,39,114,261,507,879,1404,2109,3021,4167,5574,7269,9279,11631,

%T 14352,17469,21009,24999,29466,34437,39939,45999,52644,59901,67797,

%U 76359,85614,95589,106311,117807,130104,143229,157209

%N T(n,n-3), array T as in A054120.

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,4,-1)

%F For n>3, a(n) = 3/2 * (3n^3-30n^2+107n-134).

%t LinearRecurrence[{4,-6,4,-1},{1,9,39,114,261},40] (* _Harvey P. Dale_, Sep 28 2017 *)

%o (PARI) a(n)=max(9*n^3-90*n^2+321*n-402,2)/2 \\ _Charles R Greathouse IV_, Oct 19 2022

%K nonn,easy

%O 3,2

%A _Clark Kimberling_