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A180236 a(n) = a(n-2)+a(n-4); a(1)=a(4)=101, a(2)=a(3)=10.

%I A180236 #25 Jan 04 2024 15:50:09
%S A180236 101,10,10,101,111,111,121,212,232,323,353,535,585,858,938,1393,1523,
%T A180236 2251,2461,3644,3984,5895,6445,9539,10429,15434,16874,24973,27303,
%U A180236 40407,44177,65380,71480,105787,115657,171167,187137,276954,302794,448121,489931
%N A180236 a(n) = a(n-2)+a(n-4); a(1)=a(4)=101, a(2)=a(3)=10.
%C A180236 Generalization of A115339.
%H A180236 Colin Barker, <a href="/A180236/b180236.txt">Table of n, a(n) for n = 1..1000</a>
%H A180236 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (0,1,0,1).
%F A180236 G.f.: -x*(91*x^3-91*x^2+10*x+101) / (x^4+x^2-1).  _Colin Barker_, Oct 03 2015
%t A180236 LinearRecurrence[{0,1,0,1},{101,10,10,101},50] (* _Paolo Xausa_, Jan 04 2024 *)
%o A180236 (PARI) Vec(-x*(91*x^3-91*x^2+10*x+101)/(x^4+x^2-1) + O(x^100)) \\ _Colin Barker_, Oct 03 2015
%o A180236 (PARI) a(n) = if(n==1||n==4, 101, if(n==2||n==3, 10, a(n-2)+a(n-4))); \\ _Altug Alkan_, Oct 03 2015
%Y A180236 Cf. A115339, A000045, A000032.
%K A180236 nonn,easy
%O A180236 1,1
%A A180236 _Mark Dols_, Aug 18 2010