This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A288135 #8 Mar 11 2025 04:42:05
%S A288135 1,3,5,9,18,36,72,144,288,576,1152,2304,4608,9216,18432,36864,73728,
%T A288135 147456,294911,589818,1179628,2359242,4718457,9436860,18873612,
%U A288135 37747008,75493584,150986304,301970880,603938304,1207869696,2415725568,4831423488,9662791680
%N A288135 Coefficients of 1/(Sum_{k>=0} [(k+1)*r]*(-x)^k), where r = sqrt(7/3) and [ ] = floor.
%C A288135 Conjecture: the sequence is strictly increasing.
%F A288135 G.f.: 1/(Sum_{k>=0} [(k+1)*r]*(-x)^k), where r = sqrt(7/3) and [ ] = floor.
%t A288135 r = Sqrt[7/3];
%t A288135 u = 1000; (* # initial terms from given series *)
%t A288135 v = 100; (* # coefficients in reciprocal series *)
%t A288135 CoefficientList[Series[1/Sum[Floor[r*(k + 1)] (-x)^k, {k, 0, u}], {x, 0, v}], x]
%Y A288135 Cf. A078140 (includes guide to related sequences).
%K A288135 nonn,easy
%O A288135 0,2
%A A288135 _Clark Kimberling_, Jul 10 2017