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%I #6 Jun 22 2020 19:30:03
%S 0,1,1,5,18,56,191,640,2133,7141,23881,79850,267048,893051,2986496,
%T 9987385,33399513,111693661,373522786,1249124120,4177284903,
%U 13969556096,46716587501,156228267805,522454078593,1747175898106,5842855371016,19539508829315,65343463262208
%N a(n) = 2*a(n-1) + 3*a(n-2) + 5*a(n-3), a(0) = 0, a(1) = 1, a(2) = 1.
%C In Soykan (2020), this sequences is referred to as E_n, "modified Grahaml sequence" (sic), see p. 45.
%H Michael De Vlieger, <a href="/A335720/b335720.txt">Table of n, a(n) for n = 0..1908</a>
%H Yüksel Soykan, <a href="https://doi.org/10.9734/JAMCS/2020/v35i230248">On Generalized Grahaml Numbers</a>, Journal of Advances in Mathematics and Computer Science (2020) Vol. 35, No. 2: 42-57, Article no. JAMCS.55255.
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (2,3,5).
%F G.f.: (x - x^2)/(1 - 2*x - 3*x^2 - 5*x^3).
%t LinearRecurrence[{2, 3, 5}, {0, 1, 1}, 29] (* or *)
%t CoefficientList[Series[(x - x^2)/(1 - 2 x - 3 x^2 - 5 x^3), {x, 0, 28}], x]
%Y Cf. A000032, A000045, A000073, A335718, A335719.
%K nonn,easy
%O 0,4
%A _Michael De Vlieger_, Jun 18 2020