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A185265 a(0)=1, a(1)=2; thereafter a(n) = f(n-1) + f(n-2) where f() = A164387().

%I A185265 #22 Jun 25 2017 23:03:50
%S A185265 1,2,3,6,12,22,39,70,127,231,419,759,1375,2492,4517,8187,14838,26892,
%T A185265 48739,88335,160099,290164,525894,953132,1727460,3130855,5674373,
%U A185265 10284254,18639219,33781788,61226235,110966650,201116358,364504015,660628396,1197325296,2170036700,3932982369,7128151480
%N A185265 a(0)=1, a(1)=2; thereafter a(n) = f(n-1) + f(n-2) where f() = A164387().
%C A185265 Arises in studying lunar arithmetic.
%H A185265 G. C. Greubel, <a href="/A185265/b185265.txt">Table of n, a(n) for n = 0..1000</a>
%H A185265 D. Applegate, M. LeBrun and N. J. A. Sloane, <a href="http://arxiv.org/abs/1107.1130">Dismal Arithmetic</a> [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing]
%H A185265 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,0,1,1).
%F A185265 Satisfies the same recurrence as A164387 and A079976, although with different initial conditions.
%F A185265 From _Colin Barker_, Jul 25 2013: (Start)
%F A185265 a(n) = a(n-1) + a(n-2) + a(n-4) + a(n-5) for n>5.
%F A185265 G.f.: -(x+1)*(x^4+x^3+1) / (x^5+x^4+x^2+x-1). (End)
%t A185265 CoefficientList[Series[-(x + 1)*(x^4 + x^3 + 1)/(x^5 + x^4 + x^2 + x - 1), {x, 0, 50}], x] (* _G. C. Greubel_, Jun 25 2017 *)
%o A185265 (PARI) x='x+O('x^50); Vec(-(x+1)*(x^4+x^3+1)/(x^5+x^4+x^2+x-1)) \\ _G. C. Greubel_, Jun 25 2017
%Y A185265 Cf. A164387, A079976.
%K A185265 nonn,easy
%O A185265 0,2
%A A185265 _N. J. A. Sloane_, Mar 31 2011