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%I #26 Sep 08 2022 08:45:19
%S 1,1,1,1,1,1,1,6,6,11,16,26,41,66,106,166,266,421,671,1066,1696,2696,
%T 4286,6816,10836,17231,27396,43561,69261,110126,175101,278411,442676,
%U 703856,1119136,1779431,2829306,4498611,7152816,11373016,18083156,28752316
%N a(n) = a(n-2) + a(n-3) + a(n-4) + a(n-5) + a(n-6) + a(n-7).
%H Harvey P. Dale, <a href="/A109538/b109538.txt">Table of n, a(n) for n = 0..1000</a>
%H Peter Borwein and Kevin G. Hare, <a href="http://docserver.carma.newcastle.edu.au/225/2/00_148-Borwein-Hare.pdf">Some computations on Pisot and Salem numbers</a>, 2000, table 1, p. 7.
%H Peter Borwein and Kevin G. Hare, <a href="https://doi.org/10.1090/S0025-5718-01-01336-9">Some computations on the spectra of Pisot and Salem numbers</a>, Math. Comp. 71 (2002), 767-780.
%H <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (0,1,1,1,1,1,1).
%F G.f.: (1 + x - x^3 - 2*x^4 - 3*x^5 - 4*x^6) / (1 - x^2 - x^3 - x^4 - x^5 - x^6 - x^7). - _Colin Barker_, Dec 17 2017
%t LinearRecurrence[{0,1,1,1,1,1,1},{1,1,1,1,1,1,1},50] (* _Harvey P. Dale_, Dec 29 2012 *)
%o (PARI) Vec((1 + x - x^3 - 2*x^4 - 3*x^5 - 4*x^6) / (1 - x^2 - x^3 - x^4 - x^5 - x^6 - x^7) + O(x^50)) \\ _Colin Barker_, Dec 17 2017
%o (Magma) m:=50; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!((1 + x-x^3-2*x^4-3*x^5-4*x^6)/(1-x^2-x^3-x^4-x^5-x^6-x^7))); // _G. C. Greubel_, Nov 03 2018
%Y Cf. A107479, A107480, A109543, A109544, A114749, A125950, A130844, A143335, A147851.
%K nonn,easy
%O 0,8
%A _Roger L. Bagula_, Jun 20 2005