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diff --git a/2048/DEPENDENCIES/recursion.sci b/2048/DEPENDENCIES/recursion.sci
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+// Recursive computation of Ej and Fj
+// 11.1
+
+function [Fj,dFj,Ej,dEj] = recursion(A,dA,C,dC,j)
+Fo = C; dFo = dC;
+Eo = 1; dEo = 0;
+A_z = A(2:dA+1); dA_z = dA-1;
+zi = 1; dzi = 0;
+for i = 1:j-1
+    if (dFo == 0)
+        Fn1 = 0;
+    else
+        Fn1 = Fo(2:(dFo+1));
+    end
+    dFn1 = max(dFo-1,0);
+    Fn2 = -Fo(1)*A_z;  dFn2 = dA-1;
+    [Fn,dFn] = poladd(Fn1,dFn1,Fn2,dFn2);
+    zi = convol(zi,[0,1]); dzi = dzi + 1;
+    En2 = Fn(1)*zi; dEn2 = dzi;
+    [En,dEn] = poladd(Eo,dEo,En2,dEn2);
+    Eo = En; Fo = Fn;
+    dEo = dEn; dFo = dFn;
+end
+if (dFo == 0)
+    Fn1 = 0;
+else
+Fn1 = Fo(2:(dFo+1));
+end;
+dFn1 = max(dFo-1,0);
+Fn2 = -Fo(1)*A_z;  dFn2 = dA-1;
+[Fn,dFn] = poladd(Fn1,dFn1,Fn2,dFn2);
+Fj = Fn; dFj = dFn;
+Ej = Eo; dEj = dEo;
+endfunction;
+