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%I #7 Jul 31 2015 17:26:20
%S 7,11,13,17,21,23,27,31,33,37,41,43,47,51,53,57,61,63,67,71,73,77,81,
%T 83,87,91,93,97,101,103,107,111,113,117,121,123,127,131,133,137,141,
%U 143,147,151,153,157,161,163,167,171,173,177,181,183,187,191,193,197,201
%N a(0)=7, a(1)=11, a(2)=13, a(3)=17; then a(n) = a(n-1)+a(n-3)-a(n-4).
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (1, 0, 1, -1).
%F G.f.: (-3*x^3+2*x^2+4*x+7)/((x-1)^2*(x^2+x+1)). - _Harvey P. Dale_, Aug 26 2012
%t a[0] = 7; a[1] = 11; a[2] = 13; a[3] = 17; a[n_Integer?Positive] := a[n] = a[n - 1] + a[n - 3] - a[n - 4]; aa = Table[a[n], {n, 0, 200}]
%t LinearRecurrence[{1,0,1,-1},{7,11,13,17},60] (* _Harvey P. Dale_, Aug 26 2012 *)
%K nonn
%O 0,1
%A _Roger L. Bagula_, Mar 21 2005