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%I #9 Sep 08 2019 01:24:50
%S 0,1,0,3,8,25,72,203,560,1521,4080,10835,28536,74633,194040,501915,
%T 1292512,3315425,8474976,21597091,54884200,139127289,351877416,
%U 888121195,2237336592,5626467025,14126832720,35416929267,88670846936
%N a(n) = n*Pell(n-2).
%C The signed version (-1)^(n+1)*n*Pell(n-2) is the second inverse binomial transform of A093967.
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-2,-4,-1).
%F G.f.: x(1-4x+5x^2)/(1-2x-x^2)^2;
%F a(n) = n*(1 + sqrt(2))^n*(3*sqrt(2)/4 - 1) - n*(1 - sqrt(2))^n*(3*sqrt(2)/4 + 1).
%Y Cf. A000129.
%K easy,nonn
%O 0,4
%A _Paul Barry_, Apr 21 2004
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