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 A218186 #21 Nov 22 2023 06:42:10
%S A218186 0,0,1,6,37,234,1514,9996,67181,458562,3172478,22206420,157027938,
%T A218186 1120292388,8055001716,58314533400,424740506109,3110401363122,
%U A218186 22888001498102,169155516667524,1255072594261142,9345400450314924,69812926066668044,523072984217339304,3929809142578361938,29598511892723647860
%N A218186 Number of rows with the value true in the truth tables of all bracketed formulas with n distinct propositions p_1, ..., p_n connected by the binary connective of m-implication (case 1).
%H A218186 Volkan Yildiz, <a href="http://arxiv.org/abs/1205.5595">General combinatorical structure of truth tables of bracketed formulas connected by implication</a>, arXiv preprint arXiv:1205.5595 [math.CO], 2012.
%F A218186 Yildiz gives a g.f.
%F A218186 G.f.: (1-6*x-sqrt((1-4*x)*(1-8*x)))/2. - _Michel Marcus_, Oct 21 2020
%F A218186 D-finite with recurrence n*a(n) +(n+5)*a(n-1) +(n+44)*a(n-2) +(n+331)*a(n-3) +10*(-902*n+3859)*a(n-4) +34720*(n-6)*a(n-5)=0. - _R. J. Mathar_, Nov 22 2023
%o A218186 (PARI) my(x='x+O('x^30)); concat([0,0], Vec((1-6*x-sqrt((1-4*x)*(1-8*x)))/2)) \\ _Michel Marcus_, Oct 21 2020
%Y A218186 Essentially the same as A025230.
%K A218186 nonn
%O A218186 0,4
%A A218186 _N. J. A. Sloane_, Oct 23 2012
%E A218186 a(6) corrected by _Georg Fischer_, Jun 07 2021